//
// expression.cs: Expression representation for the IL tree.
//
// Author:
//   Miguel de Icaza (miguel@ximian.com)
//   Manjula GHM (mmanjula@novell.com)
//   Satya Sudha K (ksathyasudha@novell.com)
//
// (C) 2001 Ximian, Inc.
//
//
#define USE_OLD

namespace Mono.MonoBASIC {
	using System;
	using System.Collections;
	using System.Reflection;
	using System.Reflection.Emit;
	using System.Text;

	/// <summary>
	///   This is just a helper class, it is generated by Unary, UnaryMutator
	///   when an overloaded method has been found.  It just emits the code for a
	///   static call.
	/// </summary>
	public class StaticCallExpr : ExpressionStatement {
		ArrayList args;
		MethodInfo mi;

		StaticCallExpr (MethodInfo m, ArrayList a, Location l)
		{
			mi = m;
			args = a;

			type = m.ReturnType;
			eclass = ExprClass.Value;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			//
			// We are born fully resolved
			//
			return this;
		}

		public override void Emit (EmitContext ec)
		{
			if (args != null) 
				Invocation.EmitArguments (ec, mi, args);

			ec.ig.Emit (OpCodes.Call, mi);
			return;
		}
		
		static public Expression MakeSimpleCall (EmitContext ec, MethodGroupExpr mg,
							 Expression e, Location loc)
		{
			ArrayList args;
			MethodBase method;
			
			args = new ArrayList (1);
			args.Add (new Argument (e, Argument.AType.Expression));
			method = Invocation.OverloadResolve (ec, (MethodGroupExpr) mg, args, loc);

			if (method == null)
				return null;

			return new StaticCallExpr ((MethodInfo) method, args, loc);
		}

		public override void EmitStatement (EmitContext ec)
		{
			Emit (ec);
			if (TypeManager.TypeToCoreType (type) != TypeManager.void_type)
				ec.ig.Emit (OpCodes.Pop);
		}
	}
	
	/// <summary>
	///   Unary expressions.  
	/// </summary>
	///
	/// <remarks>
	///   Unary implements unary expressions.   It derives from
	///   ExpressionStatement becuase the pre/post increment/decrement
	///   operators can be used in a statement context.
	/// </remarks>
	public class Unary : Expression {
		public enum Operator : byte {
			UnaryPlus, UnaryNegation, LogicalNot, OnesComplement,
			Indirection, AddressOf,  TOP
		}

		public Operator Oper;
		public Expression Expr;
		
		public Unary (Operator op, Expression expr, Location loc)
		{
			this.Oper = op;
			this.Expr = expr;
			this.loc = loc;
		}

		/// <summary>
		///   Returns a stringified representation of the Operator
		/// </summary>
		static public string OperName (Operator oper)
		{
			switch (oper){
			case Operator.UnaryPlus:
				return "+";
			case Operator.UnaryNegation:
				return "-";
			case Operator.LogicalNot:
				return "Not";
			case Operator.OnesComplement:
				return "~";
			case Operator.AddressOf:
				return "AddressOf";
			case Operator.Indirection:
				return "*";
			}

			return oper.ToString ();
		}

		static string [] oper_names;

		static Unary ()
		{
			oper_names = new string [(int)Operator.TOP];

			oper_names [(int) Operator.UnaryPlus] = "op_UnaryPlus";
			oper_names [(int) Operator.UnaryNegation] = "op_UnaryNegation";
			oper_names [(int) Operator.LogicalNot] = "op_LogicalNot";
			oper_names [(int) Operator.OnesComplement] = "op_OnesComplement";
			oper_names [(int) Operator.Indirection] = "op_Indirection";
			oper_names [(int) Operator.AddressOf] = "op_AddressOf";
		}

		void Error23 (Type t)
		{
			Error (
				30311, "Operator " + OperName (Oper) +
				" cannot be applied to operand of type '" +
				TypeManager.MonoBASIC_Name (t) + "'");
		}

		/// <remarks>
		///   The result has been already resolved:
		///
		///   FIXME: a minus constant -128 sbyte cant be turned into a
		///   constant byte.
		/// </remarks>
		static Expression TryReduceNegative (Constant expr)
		{
			Expression e = null;
			
			if (expr is IntConstant)
				e = new IntConstant (-((IntConstant) expr).Value);
			else if (expr is UIntConstant){
				uint value = ((UIntConstant) expr).Value;

				if (value < 2147483649)
					return new IntConstant (-(int)value);
				else
					e = new LongConstant (value);
			}
			else if (expr is LongConstant)
				e = new LongConstant (-((LongConstant) expr).Value);
			else if (expr is ULongConstant){
				ulong value = ((ULongConstant) expr).Value;

				if (value < 9223372036854775809)
					return new LongConstant(-(long)value);
			}
			else if (expr is FloatConstant)
				e = new FloatConstant (-((FloatConstant) expr).Value);
			else if (expr is DoubleConstant)
				e = new DoubleConstant (-((DoubleConstant) expr).Value);
			else if (expr is DecimalConstant)
				e = new DecimalConstant (-((DecimalConstant) expr).Value);
			else if (expr is ShortConstant)
				e = new IntConstant (-((ShortConstant) expr).Value);
			else if (expr is UShortConstant)
				e = new IntConstant (-((UShortConstant) expr).Value);
			return e;
		}

		// <summary>
		//   This routine will attempt to simplify the unary expression when the
		//   argument is a constant.  The result is returned in 'result' and the
		//   function returns true or false depending on whether a reduction
		//   was performed or not
		// </summary>
		bool Reduce (EmitContext ec, Constant e, out Expression result)
		{
			Type expr_type = e.Type;
			
			switch (Oper){
			case Operator.UnaryPlus:
				result = e;
				return true;
				
			case Operator.UnaryNegation:
				result = TryReduceNegative (e);
				return true;
				
			case Operator.LogicalNot:
				if (expr_type != TypeManager.bool_type) {
					result = null;
					Error23 (expr_type);
					return false;
				}
				
				BoolConstant b = (BoolConstant) e;
				result = new BoolConstant (!(b.Value));
				return true;
				
			case Operator.OnesComplement:
				if (!((expr_type == TypeManager.int32_type) ||
				      (expr_type == TypeManager.uint32_type) ||
				      (expr_type == TypeManager.int64_type) ||
				      (expr_type == TypeManager.uint64_type) ||
				      (expr_type.IsSubclassOf (TypeManager.enum_type)))){
					result = null;
					Error23 (expr_type);
					return false;
				}

				if (e is EnumConstant){
					EnumConstant enum_constant = (EnumConstant) e;
					Expression reduced;
					
					if (Reduce (ec, enum_constant.Child, out reduced)){
						result = new EnumConstant ((Constant) reduced, enum_constant.Type);
						return true;
					} else {
						result = null;
						return false;
					}
				}

				if (expr_type == TypeManager.int32_type){
					result = new IntConstant (~ ((IntConstant) e).Value);
				} else if (expr_type == TypeManager.uint32_type){
					result = new UIntConstant (~ ((UIntConstant) e).Value);
				} else if (expr_type == TypeManager.int64_type){
					result = new LongConstant (~ ((LongConstant) e).Value);
				} else if (expr_type == TypeManager.uint64_type){
					result = new ULongConstant (~ ((ULongConstant) e).Value);
				} else {
					result = null;
					Error23 (expr_type);
					return false;
				}
				return true;

			case Operator.AddressOf:
				result = this;
				return false;

			case Operator.Indirection:
				result = this;
				return false;
			}
			throw new Exception ("Can not constant fold: " + Oper.ToString());
		}

		Expression ResolveOperator (EmitContext ec)
		{
			Type expr_type = Expr.Type;

			Expression mg;
			string op_name;
			if (Oper == Operator.LogicalNot && expr_type != TypeManager.bool_type) 
				Oper = Operator.OnesComplement;


			if ((expr_type == TypeManager.string_type) &&
			    (Oper == Operator.UnaryPlus ||
			     Oper == Operator.UnaryNegation)) {

				Expr = ConvertImplicit (ec, Expr, TypeManager.double_type, loc);
				if (Expr == null) {
					Error23 (expr_type);
					return null;
				}
				expr_type = Expr.Type;
			}

			//
			// Step 1: Perform Operator Overload location
			//
			op_name = oper_names [(int) Oper];

			mg = MemberLookup (ec, expr_type, op_name, MemberTypes.Method, AllBindingFlags, loc);
			
			if (mg != null) {
				Expression e = StaticCallExpr.MakeSimpleCall (
					ec, (MethodGroupExpr) mg, Expr, loc);

				if (e == null){
					Error23 (expr_type);
					return null;
				}
				
				return e;
			}

			// Only perform numeric promotions on:
			// +, - 

			if (expr_type == null)
				return null;
			
			//
			// Step 2: Default operations on CLI native types.
			//

			// Attempt to use a constant folding operation.
			if (Expr is Constant){
				Expression result;
				
				if (Reduce (ec, (Constant) Expr, out result))
					return result;
			}

			switch (Oper){
			case Operator.LogicalNot:
				if (expr_type != TypeManager.bool_type) {
					Error23 (Expr.Type);
					return null;
				}
				
				type = TypeManager.bool_type;
				return this;

			case Operator.OnesComplement:
				if (expr_type == TypeManager.string_type ||
				    expr_type == TypeManager.decimal_type ||
				    expr_type == TypeManager.double_type ||
				    expr_type == TypeManager.float_type) {
					if ((Expr = ConvertImplicit (ec, Expr, TypeManager.int64_type, loc)) == null) {
						Error23 (Expr.Type);
						return null;
					}
					expr_type = Expr.Type;
				}

				if (expr_type == TypeManager.int64_type) {
					type = expr_type;
					return this;
				}
				if (expr_type == TypeManager.byte_type ||
				    expr_type == TypeManager.short_type ||
				    expr_type == TypeManager.int32_type) {
					type = TypeManager.int32_type;
					return this;
				}

				if (expr_type == TypeManager.object_type) {
					Expression etmp = Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.ObjectType.NotObj", Location.Null);
					ArrayList arguments = new ArrayList ();
					arguments.Add (new Argument (Expr, Argument.AType.Expression));
					Expression e = new Invocation (etmp, arguments, loc);
					return e.Resolve (ec);
				}

				break;
			case Operator.AddressOf:
				// Not required in VB ??
				if (Expr.eclass != ExprClass.Variable){
					Error (211, "Cannot take the address of non-variables");
					return null;
				}
				
				if (!ec.InUnsafe) {
					UnsafeError (loc); 
					return null;
				}
				
				if (!TypeManager.VerifyUnManaged (Expr.Type, loc)){
					return null;
				}
				
				string ptr_type_name = Expr.Type.FullName + "*";
				type = TypeManager.LookupType (ptr_type_name);
				
				return this;

			case Operator.Indirection:
				if (!ec.InUnsafe){
					UnsafeError (loc);
					return null;
				}
				
				if (!expr_type.IsPointer){
					Error (
						193,
						"The * or -> operator can only be applied to pointers");
					return null;
				}
				
				//
				// We create an Indirection expression, because
				// it can implement the IMemoryLocation.
				// 
				return new Indirection (Expr, loc);
			
			case Operator.UnaryPlus:
				//
				// A plus in front of something is just a no-op, so return the child.
				//
				if (expr_type == TypeManager.string_type) {
					Expression e = ConvertImplicit (ec, Expr, TypeManager.double_type, loc);
					if (e != null){
						type = TypeManager.double_type;
						return e;
					}
				}

				if (expr_type == TypeManager.bool_type) {
					Expression e = ConvertImplicit (ec, Expr, TypeManager.short_type, loc);
					if (e != null){
						type = TypeManager.int32_type;
						return e;
					}
				}

				return Expr;

			case Operator.UnaryNegation:
				//
				// Deals with -literals
				// int     operator- (int x)
				// long    operator- (long x)
				// float   operator- (float f)
				// double  operator- (double d)
				// decimal operator- (decimal d)
				//

				//
				// transform - - expr into expr
				//
				if (Expr is Unary){
					Unary unary = (Unary) Expr;
					
					if (unary.Oper == Operator.UnaryNegation)
						return unary.Expr;
				}

				//
				// perform numeric promotions to int,
				// long, double.
				//
				//
				// The following is inneficient, because we call
				// ConvertImplicit too many times.
				//
				// It is also not clear if we should convert to Float
				// or Double initially.
				//
				if (expr_type == TypeManager.string_type) {
					Expression e = ConvertImplicit (ec, Expr, TypeManager.double_type, loc);
					if (e != null){
						Expr = e;
						type = TypeManager.double_type;
						return this;
					}
				}

				if (expr_type == TypeManager.bool_type) {
					Expression e = ConvertImplicit (ec, Expr, TypeManager.short_type, loc);
					if (e != null){
						Expr = e;
						type = TypeManager.int32_type;
						return this;
					}
				}

				if (expr_type == TypeManager.float_type || 
				    expr_type == TypeManager.double_type) {
					type = expr_type;
					return this;
				}

				if (expr_type == TypeManager.short_type ||
				    expr_type == TypeManager.byte_type) { 
					type = TypeManager.int32_type;
					return this;
				}

				if (expr_type == TypeManager.int32_type || 
				    expr_type == TypeManager.int64_type) {
					Expression e = new Binary (Binary.Operator.Subtraction, new IntLiteral (0), Expr, loc);
					return e.Resolve (ec);
				}
				
				Error23 (expr_type);
				return null;
			}

			Error (187, "No such operator '" + OperName (Oper) + "' defined for type '" +
			       TypeManager.MonoBASIC_Name (expr_type) + "'");
			return null;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			if (Oper == Operator.AddressOf)
				Expr = Expr.ResolveLValue (ec, new EmptyExpression ());
			else
				Expr = Expr.Resolve (ec);
			
			if (Expr == null)
				return null;

			Type init_type = Expr.Type;

			eclass = ExprClass.Value;
			Expression etmp = ResolveOperator (ec);
			// Convert the result to byte/short if operands are of type byte/short/boolean
			if (etmp.Type != init_type && 
			    (init_type == TypeManager.byte_type || 
			     init_type == TypeManager.short_type || 
			     init_type == TypeManager.bool_type)) {
				Expression conv_exp = null;
				if (init_type == TypeManager.byte_type && Oper != Operator.UnaryNegation) {
					return new OpcodeCast (etmp, TypeManager.byte_type, OpCodes.Conv_U1);
				}
				else
					conv_exp = ConvertImplicit (ec, etmp, TypeManager.short_type, loc);

				if (conv_exp != null)
					return conv_exp;
			}
			return etmp;
		}

		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;
			
			switch (Oper) {
			case Operator.UnaryPlus:
				throw new Exception ("This should be caught by Resolve");
				
			case Operator.UnaryNegation:
				Expr.Emit (ec);
				ig.Emit (OpCodes.Neg);
				break;
				
			case Operator.LogicalNot:
				Expr.Emit (ec);
				ig.Emit (OpCodes.Ldc_I4_0);
				ig.Emit (OpCodes.Ceq);
				break;
				
			case Operator.OnesComplement:
				Expr.Emit (ec);
				ig.Emit (OpCodes.Not);
				break;
				
			case Operator.AddressOf:
				((IMemoryLocation)Expr).AddressOf (ec, AddressOp.LoadStore);
				break;
				
			default:
				throw new Exception ("This should not happen: Operator = "
						     + Oper.ToString ());
			}
		}

		/// <summary>
		///   This will emit the child expression for 'ec' avoiding the logical
		///   not.  The parent will take care of changing brfalse/brtrue
		/// </summary>
		public void EmitLogicalNot (EmitContext ec)
		{
			if (Oper != Operator.LogicalNot)
				throw new Exception ("EmitLogicalNot can only be called with !expr");

			Expr.Emit (ec);
		}

		public override string ToString ()
		{
			return "Unary (" + Oper + ", " + Expr + ")";
		}
		
	}

	//
	// Unary operators are turned into Indirection expressions
	// after semantic analysis (this is so we can take the address
	// of an indirection).
	//
	public class Indirection : Expression, IMemoryLocation, IAssignMethod {
		Expression expr;
		LocalTemporary temporary;
		bool have_temporary;
		
		public Indirection (Expression expr, Location l)
		{
			this.expr = expr;
			this.type = TypeManager.TypeToCoreType (expr.Type.GetElementType ());
			eclass = ExprClass.Variable;
			loc = l;
		}

/*
		void LoadExprValue (EmitContext ec)
		{
		}
*/
		
		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;

			if (temporary != null){
				if (have_temporary){
					temporary.Emit (ec);
					return;
				}
				expr.Emit (ec);
				ec.ig.Emit (OpCodes.Dup);
				temporary.Store (ec);
				have_temporary = true;
			} else
				expr.Emit (ec);
			
			LoadFromPtr (ig, Type);
		}

		public void EmitAssign (EmitContext ec, Expression source)
		{
			if (temporary != null){
				if (have_temporary){
					temporary.Emit (ec);
					return;
				}
				expr.Emit (ec);
				ec.ig.Emit (OpCodes.Dup);
				temporary.Store (ec);
				have_temporary = true;
			} else
				expr.Emit (ec);

			source.Emit (ec);
			StoreFromPtr (ec.ig, type);
		}
		
		public void AddressOf (EmitContext ec, AddressOp Mode)
		{
			if (temporary != null){
				if (have_temporary){
					temporary.Emit (ec);
					return;
				}
				expr.Emit (ec);
				ec.ig.Emit (OpCodes.Dup);
				temporary.Store (ec);
				have_temporary = true;
			} else
				expr.Emit (ec);
		}

		public override Expression DoResolve (EmitContext ec)
		{
			//
			// Born fully resolved
			//
			return this;
		}

		public new void CacheTemporaries (EmitContext ec)
		{
			temporary = new LocalTemporary (ec, type);
		}
	}
	
	/// <summary>
	///   Unary Mutator expressions (pre and post ++ and --)
	/// </summary>
	///
	/// <remarks>
	///   UnaryMutator implements ++ and -- expressions.   It derives from
	///   ExpressionStatement becuase the pre/post increment/decrement
	///   operators can be used in a statement context.
	///
	/// FIXME: Idea, we could split this up in two classes, one simpler
	/// for the common case, and one with the extra fields for more complex
	/// classes (indexers require temporary access;  overloaded require method)
	///
	/// Maybe we should have classes PreIncrement, PostIncrement, PreDecrement,
	/// PostDecrement, that way we could save the 'Mode' byte as well.  
	/// </remarks>
	public class UnaryMutator : ExpressionStatement {
		public enum Mode : byte {
			PreIncrement, PreDecrement, PostIncrement, PostDecrement
		}
		
		Mode mode;
		Expression expr;
		LocalTemporary temp_storage;

		//
		// This is expensive for the simplest case.
		//
		Expression method;
			
		public UnaryMutator (Mode m, Expression e, Location l)
		{
			mode = m;
			loc = l;
			expr = e;
		}

		static string OperName (Mode mode)
		{
			return (mode == Mode.PreIncrement || mode == Mode.PostIncrement) ?
				"++" : "--";
		}
		
		/// <summary>
		///   Returns whether an object of type 't' can be incremented
		///   or decremented with add/sub (ie, basically whether we can
		///   use pre-post incr-decr operations on it, but it is not a
		///   System.Decimal, which we require operator overloading to catch)
		/// </summary>
		static bool IsIncrementableNumber (Type t)
		{
			return (t == TypeManager.sbyte_type) ||
				(t == TypeManager.byte_type) ||
				(t == TypeManager.short_type) ||
				(t == TypeManager.ushort_type) ||
				(t == TypeManager.int32_type) ||
				(t == TypeManager.uint32_type) ||
				(t == TypeManager.int64_type) ||
				(t == TypeManager.uint64_type) ||
				(t == TypeManager.char_type) ||
				(t.IsSubclassOf (TypeManager.enum_type)) ||
				(t == TypeManager.float_type) ||
				(t == TypeManager.double_type) ||
				(t.IsPointer && t != TypeManager.void_ptr_type);
		}

		Expression ResolveOperator (EmitContext ec)
		{
			Type expr_type = expr.Type;

			//
			// Step 1: Perform Operator Overload location
			//
			Expression mg;
			string op_name;
			
			if (mode == Mode.PreIncrement || mode == Mode.PostIncrement)
				op_name = "op_Increment";
			else 
				op_name = "op_Decrement";

			mg = MemberLookup (ec, expr_type, op_name, MemberTypes.Method, AllBindingFlags, loc);

			if (mg == null && expr_type.BaseType != null)
				mg = MemberLookup (ec, expr_type.BaseType, op_name,
						   MemberTypes.Method, AllBindingFlags, loc);
			
			if (mg != null) {
				method = StaticCallExpr.MakeSimpleCall (
					ec, (MethodGroupExpr) mg, expr, loc);

				type = method.Type;
				return this;
			}

			//
			// The operand of the prefix/postfix increment decrement operators
			// should be an expression that is classified as a variable,
			// a property access or an indexer access
			//
			type = expr_type;
			if (expr.eclass == ExprClass.Variable){
				if (IsIncrementableNumber (expr_type) ||
				    expr_type == TypeManager.decimal_type){
					return this;
				}
			} else if (expr.eclass == ExprClass.IndexerAccess){
				IndexerAccess ia = (IndexerAccess) expr;
				
				temp_storage = new LocalTemporary (ec, expr.Type);
				
				expr = ia.ResolveLValue (ec, temp_storage);
				if (expr == null)
					return null;

				return this;
			} else if (expr.eclass == ExprClass.PropertyAccess){
				PropertyExpr pe = (PropertyExpr) expr;

				if (pe.VerifyAssignable ())
					return this;

				return null;
			} else {
				expr.Error118 ("variable, indexer or property access");
				return null;
			}

			Error (187, "No such operator '" + OperName (mode) + "' defined for type '" +
			       TypeManager.MonoBASIC_Name (expr_type) + "'");
			return null;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			expr = expr.Resolve (ec);
			
			if (expr == null)
				return null;

			eclass = ExprClass.Value;
			return ResolveOperator (ec);
		}

		static int PtrTypeSize (Type t)
		{
			return GetTypeSize (t.GetElementType ());
		}

		//
		// Loads the proper "1" into the stack based on the type
		//
		static void LoadOne (ILGenerator ig, Type t)
		{
			if (t == TypeManager.uint64_type || t == TypeManager.int64_type)
				ig.Emit (OpCodes.Ldc_I8, 1L);
			else if (t == TypeManager.double_type)
				ig.Emit (OpCodes.Ldc_R8, 1.0);
			else if (t == TypeManager.float_type)
				ig.Emit (OpCodes.Ldc_R4, 1.0F);
			else if (t.IsPointer){
				int n = PtrTypeSize (t);
				
				if (n == 0)
					ig.Emit (OpCodes.Sizeof, t);
				else
					IntConstant.EmitInt (ig, n);
			} else 
				ig.Emit (OpCodes.Ldc_I4_1);
		}

		
		//
		// FIXME: We need some way of avoiding the use of temp_storage
		// for some types of storage (parameters, local variables,
		// static fields) and single-dimension array access.
		//
		void EmitCode (EmitContext ec, bool is_expr)
		{
			ILGenerator ig = ec.ig;
			IAssignMethod ia = (IAssignMethod) expr;
			Type expr_type = expr.Type;
			
			if (temp_storage == null)
				temp_storage = new LocalTemporary (ec, expr_type);

			ia.CacheTemporaries (ec);
			ig.Emit (OpCodes.Nop);
			switch (mode){
			case Mode.PreIncrement:
			case Mode.PreDecrement:
				if (method == null){
					expr.Emit (ec);

					LoadOne (ig, expr_type);
					
					//
					// Select the opcode based on the check state (then the type)
					// and the actual operation
					//
					if (ec.CheckState){
						if (expr_type == TypeManager.int32_type ||
						    expr_type == TypeManager.int64_type){
							if (mode == Mode.PreDecrement)
								ig.Emit (OpCodes.Sub_Ovf);
							else
								ig.Emit (OpCodes.Add_Ovf);
						} else if (expr_type == TypeManager.uint32_type ||
							   expr_type == TypeManager.uint64_type){
							if (mode == Mode.PreDecrement)
								ig.Emit (OpCodes.Sub_Ovf_Un);
							else
								ig.Emit (OpCodes.Add_Ovf_Un);
						} else {
							if (mode == Mode.PreDecrement)
								ig.Emit (OpCodes.Sub_Ovf);
							else
								ig.Emit (OpCodes.Add_Ovf);
						}
					} else {
						if (mode == Mode.PreDecrement)
							ig.Emit (OpCodes.Sub);
						else
							ig.Emit (OpCodes.Add);
					}
				} else 
					method.Emit (ec);

				temp_storage.Store (ec);
				ia.EmitAssign (ec, temp_storage);
				if (is_expr)
					temp_storage.Emit (ec);
				break;
				
			case Mode.PostIncrement:
			case Mode.PostDecrement:
				if (is_expr)
					expr.Emit (ec);
				
				if (method == null){
					if (!is_expr)
						expr.Emit (ec);
					else
						ig.Emit (OpCodes.Dup);

					LoadOne (ig, expr_type);
					
					if (ec.CheckState){
						if (expr_type == TypeManager.int32_type ||
						    expr_type == TypeManager.int64_type){
							if (mode == Mode.PostDecrement)
								ig.Emit (OpCodes.Sub_Ovf);
							else
								ig.Emit (OpCodes.Add_Ovf);
						} else if (expr_type == TypeManager.uint32_type ||
							   expr_type == TypeManager.uint64_type){
							if (mode == Mode.PostDecrement)
								ig.Emit (OpCodes.Sub_Ovf_Un);
							else
								ig.Emit (OpCodes.Add_Ovf_Un);
						} else {
							if (mode == Mode.PostDecrement)
								ig.Emit (OpCodes.Sub_Ovf);
							else
								ig.Emit (OpCodes.Add_Ovf);
						}
					} else {
						if (mode == Mode.PostDecrement)
							ig.Emit (OpCodes.Sub);
						else
							ig.Emit (OpCodes.Add);
					}
				} else {
					method.Emit (ec);
				}
				
				temp_storage.Store (ec);
				ia.EmitAssign (ec, temp_storage);
				break;
			}
		}

		public override void Emit (EmitContext ec)
		{
			EmitCode (ec, true);
			
		}
		
		public override void EmitStatement (EmitContext ec)
		{
			EmitCode (ec, false);
		}

	}

	/// <summary>
	///   Base class for the 'Is' and 'As' classes. 
	/// </summary>
	///
	/// <remarks>
	///   FIXME: Split this in two, and we get to save the 'Operator' Oper
	///   size. 
	/// </remarks>
	public abstract class Probe : Expression {
		public readonly Expression ProbeType;
		protected Expression expr;
		protected Type probe_type;
		
		public Probe (Expression expr, Expression probe_type, Location l)
		{
			ProbeType = probe_type;
			loc = l;
			this.expr = expr;
		}

		public Expression Expr {
			get {
				return expr;
			}
		}

		public override Expression DoResolve (EmitContext ec)
		{
			 probe_type = ec.DeclSpace.ResolveType (ProbeType, false, loc);

			if (probe_type == null)
				return null;

			expr = expr.Resolve (ec);
			
			return this;
		}
	}

	/// <summary>
	///   Implementation of the 'is' operator.
	/// </summary>
	public class Is : Probe {
		public Is (Expression expr, Expression probe_type, Location l)
			: base (expr, probe_type, l)
		{
		}

		enum Action {
			AlwaysTrue, AlwaysNull, AlwaysFalse, LeaveOnStack, Probe
		}

		Action action;
		
		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;

			expr.Emit (ec);

			switch (action){
			case Action.AlwaysFalse:
				ig.Emit (OpCodes.Pop);
				IntConstant.EmitInt (ig, 0);
				return;
			case Action.AlwaysTrue:
				ig.Emit (OpCodes.Pop);
				ig.Emit (OpCodes.Nop);
				IntConstant.EmitInt (ig, 1);
				return;
			case Action.LeaveOnStack:
				// the 'e != null' rule.
				return;
			case Action.Probe:
				ig.Emit (OpCodes.Isinst, probe_type);
				ig.Emit (OpCodes.Ldnull);
				ig.Emit (OpCodes.Cgt_Un);
				return;
			}
			throw new Exception ("never reached");
		}

		public override Expression DoResolve (EmitContext ec)
		{
			Expression e = base.DoResolve (ec);

			if ((e == null) || (expr == null))
				return null;

			Type etype = expr.Type;
			bool warning_always_matches = false;
			bool warning_never_matches = false;

			type = TypeManager.bool_type;
			eclass = ExprClass.Value;

			//
			// First case, if at compile time, there is an implicit conversion
			// then e != null (objects) or true (value types)
			//
			e = ConvertImplicitStandard (ec, expr, probe_type, loc);
			if (e != null){
				expr = e;
				if (etype.IsValueType)
					action = Action.AlwaysTrue;
				else
					action = Action.LeaveOnStack;

				warning_always_matches = true;
			} else if (ExplicitReferenceConversionExists (etype, probe_type)){
				//
				// Second case: explicit reference convresion
				//
				if (expr is NullLiteral)
					action = Action.AlwaysFalse;
				else
					action = Action.Probe;
			} else {
				action = Action.AlwaysFalse;
				warning_never_matches = true;
			}
			
			if (RootContext.WarningLevel >= 1){
				if (warning_always_matches)
					Warning (
						183,
						"The expression is always of type '" +
						TypeManager.MonoBASIC_Name (probe_type) + "'");
				else if (warning_never_matches){
					if (!(probe_type.IsInterface || expr.Type.IsInterface))
						Warning (
							184,
							"The expression is never of type '" +
							TypeManager.MonoBASIC_Name (probe_type) + "'");
				}
			}

			return this;
		}				
	}

	/// <summary>
	///   Implementation of the 'as' operator.
	/// </summary>
	public class As : Probe {
		public As (Expression expr, Expression probe_type, Location l)
			: base (expr, probe_type, l)
		{
		}

		bool do_isinst = false;
		
		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;

			expr.Emit (ec);

			if (do_isinst)
				ig.Emit (OpCodes.Isinst, probe_type);
		}

		static void Error_CannotConvertType (Type source, Type target, Location loc)
		{
			Report.Error (
				39, loc, "as operator can not convert from '" +
				TypeManager.MonoBASIC_Name (source) + "' to '" +
				TypeManager.MonoBASIC_Name (target) + "'");
		}
		
		public override Expression DoResolve (EmitContext ec)
		{
			Expression e = base.DoResolve (ec);

			if (e == null)
				return null;

			type = probe_type;
			eclass = ExprClass.Value;
			Type etype = expr.Type;

			if (TypeManager.IsValueType (probe_type)){
				Report.Error (77, loc, "The as operator should be used with a reference type only (" +
					      TypeManager.MonoBASIC_Name (probe_type) + " is a value type)");
				return null;
			
			}
			
			e = ConvertImplicit (ec, expr, probe_type, loc);
			if (e != null){
				expr = e;
				do_isinst = false;
				return this;
			}

			if (ExplicitReferenceConversionExists (etype, probe_type)){
				do_isinst = true;
				return this;
			}

			Error_CannotConvertType (etype, probe_type, loc);
			return null;
		}				
	}
	
	/// <summary>
	///   This represents a typecast in the source language.
	///
	///   FIXME: Cast expressions have an unusual set of parsing
	///   rules, we need to figure those out.
	/// </summary>
	public class Cast : Expression {
		Expression target_type;
		Expression expr;
		bool runtime_cast;
			
		public Cast (Expression cast_type, Expression expr, Location loc)
		{
			this.target_type = cast_type;
			this.expr = expr;
			this.loc = loc;
			runtime_cast = false;
		}

		public Expression TargetType {
			get {
				return target_type;
			}
		}

		public Expression Expr {
			get {
				return expr;
			}
			set {
				expr = value;
			}
		}

		public bool IsRuntimeCast
		{
			get {
				return runtime_cast;
			}
			set{
				runtime_cast = value;
			}
		}

		/// <summary>
		///   Attempts to do a compile-time folding of a constant cast.
		/// </summary>
		Expression TryReduce (EmitContext ec, Type target_type)
		{
			if (expr is ByteConstant){
				byte v = ((ByteConstant) expr).Value;
	
				if (target_type == TypeManager.sbyte_type)
					return new SByteConstant ((sbyte) v);
				if (target_type == TypeManager.short_type)
					return new ShortConstant ((short) v);
				if (target_type == TypeManager.ushort_type)
					return new UShortConstant ((ushort) v);
				if (target_type == TypeManager.int32_type)
					return new IntConstant ((int) v);
				if (target_type == TypeManager.uint32_type)
					return new UIntConstant ((uint) v);
				if (target_type == TypeManager.int64_type)
					return new LongConstant ((long) v);
				if (target_type == TypeManager.uint64_type)
					return new ULongConstant ((ulong) v);
				if (target_type == TypeManager.float_type)
					return new FloatConstant ((float) v);
				if (target_type == TypeManager.double_type)
					return new DoubleConstant ((double) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}
			if (expr is SByteConstant){
				sbyte v = ((SByteConstant) expr).Value;
	
				if (target_type == TypeManager.byte_type)
					return new ByteConstant ((byte) v);
				if (target_type == TypeManager.short_type)
					return new ShortConstant ((short) v);
				if (target_type == TypeManager.ushort_type)
					return new UShortConstant ((ushort) v);
				if (target_type == TypeManager.int32_type)
					return new IntConstant ((int) v);
				if (target_type == TypeManager.uint32_type)
					return new UIntConstant ((uint) v);
				if (target_type == TypeManager.int64_type)
					return new LongConstant ((long) v);
				if (target_type == TypeManager.uint64_type)
					return new ULongConstant ((ulong) v);
				if (target_type == TypeManager.float_type)
					return new FloatConstant ((float) v);
				if (target_type == TypeManager.double_type)
					return new DoubleConstant ((double) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}
			if (expr is ShortConstant){
				short v = ((ShortConstant) expr).Value;
	
				if (target_type == TypeManager.byte_type)
					return new ByteConstant ((byte) v);
				if (target_type == TypeManager.sbyte_type)
					return new SByteConstant ((sbyte) v);
				if (target_type == TypeManager.ushort_type)
					return new UShortConstant ((ushort) v);
				if (target_type == TypeManager.int32_type)
					return new IntConstant ((int) v);
				if (target_type == TypeManager.uint32_type)
					return new UIntConstant ((uint) v);
				if (target_type == TypeManager.int64_type)
					return new LongConstant ((long) v);
				if (target_type == TypeManager.uint64_type)
					return new ULongConstant ((ulong) v);
				if (target_type == TypeManager.float_type)
					return new FloatConstant ((float) v);
				if (target_type == TypeManager.double_type)
					return new DoubleConstant ((double) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}
			if (expr is UShortConstant){
				ushort v = ((UShortConstant) expr).Value;
	
				if (target_type == TypeManager.byte_type)
					return new ByteConstant ((byte) v);
				if (target_type == TypeManager.sbyte_type)
					return new SByteConstant ((sbyte) v);
				if (target_type == TypeManager.short_type)
					return new ShortConstant ((short) v);
				if (target_type == TypeManager.int32_type)
					return new IntConstant ((int) v);
				if (target_type == TypeManager.uint32_type)
					return new UIntConstant ((uint) v);
				if (target_type == TypeManager.int64_type)
					return new LongConstant ((long) v);
				if (target_type == TypeManager.uint64_type)
					return new ULongConstant ((ulong) v);
				if (target_type == TypeManager.float_type)
					return new FloatConstant ((float) v);
				if (target_type == TypeManager.double_type)
					return new DoubleConstant ((double) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}
			if (expr is IntConstant){
				int v = ((IntConstant) expr).Value;
	
				if (target_type == TypeManager.byte_type)
					return new ByteConstant ((byte) v);
				if (target_type == TypeManager.sbyte_type)
					return new SByteConstant ((sbyte) v);
				if (target_type == TypeManager.short_type)
					return new ShortConstant ((short) v);
				if (target_type == TypeManager.ushort_type)
					return new UShortConstant ((ushort) v);
				if (target_type == TypeManager.uint32_type)
					return new UIntConstant ((uint) v);
				if (target_type == TypeManager.int64_type)
					return new LongConstant ((long) v);
				if (target_type == TypeManager.uint64_type)
					return new ULongConstant ((ulong) v);
				if (target_type == TypeManager.float_type)
					return new FloatConstant ((float) v);
				if (target_type == TypeManager.double_type)
					return new DoubleConstant ((double) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}
			if (expr is UIntConstant){
				uint v = ((UIntConstant) expr).Value;
	
				if (target_type == TypeManager.byte_type)
					return new ByteConstant ((byte) v);
				if (target_type == TypeManager.sbyte_type)
					return new SByteConstant ((sbyte) v);
				if (target_type == TypeManager.short_type)
					return new ShortConstant ((short) v);
				if (target_type == TypeManager.ushort_type)
					return new UShortConstant ((ushort) v);
				if (target_type == TypeManager.int32_type)
					return new IntConstant ((int) v);
				if (target_type == TypeManager.int64_type)
					return new LongConstant ((long) v);
				if (target_type == TypeManager.uint64_type)
					return new ULongConstant ((ulong) v);
				if (target_type == TypeManager.float_type)
					return new FloatConstant ((float) v);
				if (target_type == TypeManager.double_type)
					return new DoubleConstant ((double) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}
			if (expr is LongConstant){
				long v = ((LongConstant) expr).Value;
	
				if (target_type == TypeManager.byte_type)
					return new ByteConstant ((byte) v);
				if (target_type == TypeManager.sbyte_type)
					return new SByteConstant ((sbyte) v);
				if (target_type == TypeManager.short_type)
					return new ShortConstant ((short) v);
				if (target_type == TypeManager.ushort_type)
					return new UShortConstant ((ushort) v);
				if (target_type == TypeManager.int32_type)
					return new IntConstant ((int) v);
				if (target_type == TypeManager.uint32_type)
					return new UIntConstant ((uint) v);
				if (target_type == TypeManager.uint64_type)
					return new ULongConstant ((ulong) v);
				if (target_type == TypeManager.float_type)
					return new FloatConstant ((float) v);
				if (target_type == TypeManager.double_type)
					return new DoubleConstant ((double) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}
			if (expr is ULongConstant){
				ulong v = ((ULongConstant) expr).Value;
	
				if (target_type == TypeManager.byte_type)
					return new ByteConstant ((byte) v);
				if (target_type == TypeManager.sbyte_type)
					return new SByteConstant ((sbyte) v);
				if (target_type == TypeManager.short_type)
					return new ShortConstant ((short) v);
				if (target_type == TypeManager.ushort_type)
					return new UShortConstant ((ushort) v);
				if (target_type == TypeManager.int32_type)
					return new IntConstant ((int) v);
				if (target_type == TypeManager.uint32_type)
					return new UIntConstant ((uint) v);
				if (target_type == TypeManager.int64_type)
					return new LongConstant ((long) v);
				if (target_type == TypeManager.float_type)
					return new FloatConstant ((float) v);
				if (target_type == TypeManager.double_type)
					return new DoubleConstant ((double) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}
			if (expr is FloatConstant){
				float v = ((FloatConstant) expr).Value;
	
				if (target_type == TypeManager.byte_type)
					return new ByteConstant ((byte) v);
				if (target_type == TypeManager.sbyte_type)
					return new SByteConstant ((sbyte) v);
				if (target_type == TypeManager.short_type)
					return new ShortConstant ((short) v);
				if (target_type == TypeManager.ushort_type)
					return new UShortConstant ((ushort) v);
				if (target_type == TypeManager.int32_type)
					return new IntConstant ((int) v);
				if (target_type == TypeManager.uint32_type)
					return new UIntConstant ((uint) v);
				if (target_type == TypeManager.int64_type)
					return new LongConstant ((long) v);
				if (target_type == TypeManager.uint64_type)
					return new ULongConstant ((ulong) v);
				if (target_type == TypeManager.double_type)
					return new DoubleConstant ((double) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}
			if (expr is DoubleConstant){
				double v = ((DoubleConstant) expr).Value;
	
				if (target_type == TypeManager.byte_type)
					return new ByteConstant ((byte) v);
				if (target_type == TypeManager.sbyte_type)
					return new SByteConstant ((sbyte) v);
				if (target_type == TypeManager.short_type)
					return new ShortConstant ((short) v);
				if (target_type == TypeManager.ushort_type)
					return new UShortConstant ((ushort) v);
				if (target_type == TypeManager.int32_type)
					return new IntConstant ((int) v);
				if (target_type == TypeManager.uint32_type)
					return new UIntConstant ((uint) v);
				if (target_type == TypeManager.int64_type)
					return new LongConstant ((long) v);
				if (target_type == TypeManager.uint64_type)
					return new ULongConstant ((ulong) v);
				if (target_type == TypeManager.float_type)
					return new FloatConstant ((float) v);
				if (target_type == TypeManager.char_type)
					return new CharConstant ((char) v);
				if (target_type == TypeManager.decimal_type)
					return new DecimalConstant ((decimal) v);
			}

			return null;
		}
		
		public override Expression DoResolve (EmitContext ec)
		{
			expr = expr.Resolve (ec);
			if (expr == null)
				return null;

			type = ec.DeclSpace.ResolveType (target_type, false, Location);

			if (type == null)
				return null;

			eclass = ExprClass.Value;
			
			if (expr is Constant){
				Expression e = TryReduce (ec, type);

				if (e != null)
					return e;
			}
			
			expr = ConvertExplicit (ec, expr, type, runtime_cast, loc);
			return expr;
		}

		public override void Emit (EmitContext ec)
		{
			//
			// This one will never happen
			//
			throw new Exception ("Should not happen");
		}
	}

        public class StringConcat : Expression {

		Expression left, right;
		ArrayList Arguments; 
		protected MethodBase method;
	
		public StringConcat(Location loc, Expression left, Expression right) {
			this.left = left;
			this.right = right;
			this.loc = loc;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			left = left.Resolve (ec);
			right = right.Resolve (ec);

			if (left == null || right == null)
				return null;

			if (left.Type == null)
				throw new Exception (
					"Resolve returned non null, but did not set the type! (" +
					left + ") at Line: " + loc.Row);
			if (right.Type == null)
				throw new Exception (
					"Resolve returned non null, but did not set the type! (" +
					right + ") at Line: "+ loc.Row);

			eclass = ExprClass.Value;
			if (left is StringConstant && right is StringConstant){
				return new StringConstant (
							   ((StringConstant) left).Value +
							   ((StringConstant) right).Value);
			}
			
			Type l = left.Type;
			Type r = right.Type;

			if (l == TypeManager.string_type && r == TypeManager.string_type) {
				type = TypeManager.string_type;
				method = TypeManager.string_concat_string_string;
				Arguments = new ArrayList ();
				Arguments.Add (new Argument (left, Argument.AType.Expression));
				Arguments.Add (new Argument (right, Argument.AType.Expression));
				return this;
			}

			if (l != TypeManager.string_type) {
				method = TypeManager.string_concat_object_object;
				left = ConvertImplicit (ec, left, TypeManager.string_type, loc);
				if (left == null){
					Error_OperatorCannotBeApplied (loc, "&", l, r);
					return null;
				}
                                        
				type = TypeManager.string_type;
				Arguments = new ArrayList ();
				Arguments.Add (new Argument (left, Argument.AType.Expression));
				Arguments.Add (new Argument (right, Argument.AType.Expression));
				return this;
			}

			if (r != TypeManager.string_type) {
				method = TypeManager.string_concat_object_object;
				right = ConvertImplicit (ec, right, TypeManager.string_type, loc);
				if (right == null){
					Error_OperatorCannotBeApplied (loc, "&", l, r);
					return null;
				}
                                        
				type = TypeManager.string_type;
				Arguments = new ArrayList ();
				Arguments.Add (new Argument (left, Argument.AType.Expression));
				Arguments.Add (new Argument (right, Argument.AType.Expression));
				return this;
			}
			return this;
		}

                public override void Emit (EmitContext ec)
                {
                        ILGenerator ig = ec.ig;
                        if (method != null) {
                                // Note that operators are static anyway
                                if (Arguments != null)
                                        Invocation.EmitArguments (ec, method, Arguments);
                                if (method is MethodInfo)
                                        ig.Emit (OpCodes.Call, (MethodInfo) method);
                                else
                                        ig.Emit (OpCodes.Call, (ConstructorInfo) method);

                                return;
                        }
		}

                static public void Error_OperatorCannotBeApplied (Location loc, string name, Type l, Type r)
                {  
	                 Report.Error (19, loc,
                               "Operator " + name + " cannot be applied to operands of type '" +
                               TypeManager.MonoBASIC_Name (l) + "' and '" +
                               TypeManager.MonoBASIC_Name (r) + "'");
                }

        }


	/// <summary>
	///   Binary operators
	/// </summary>
	public class Binary : Expression {
		public enum Operator : byte {
			Exponentiation,
			Multiply, Division, IntDivision, Modulus,
			Addition, Subtraction,
			LeftShift, RightShift,
			LessThan, GreaterThan, LessThanOrEqual, GreaterThanOrEqual, 
			Equality, Inequality,
			Like,
			BitwiseAnd,
			ExclusiveOr,
			BitwiseOr,
			LogicalAnd,
			LogicalOr,
			Is,
			TOP
		}

		Operator oper;
		Expression left, right;

		//
		// After resolution, method might contain the operator overload
		// method.
		//
		protected MethodBase method;
		ArrayList  Arguments;

		bool DelegateOperation;

		// This must be kept in sync with Operator!!!
		static string [] oper_names;

		static Binary ()
		{
			oper_names = new string [(int) Operator.TOP];

			oper_names [(int) Operator.Multiply] = "op_Multiply";
			oper_names [(int) Operator.Division] = "op_Division";
			oper_names [(int) Operator.IntDivision] = "op_Division";
			oper_names [(int) Operator.Modulus] = "op_Modulus";
			oper_names [(int) Operator.Addition] = "op_Addition";
			oper_names [(int) Operator.Subtraction] = "op_Subtraction";
			oper_names [(int) Operator.LeftShift] = "op_LeftShift";
			oper_names [(int) Operator.RightShift] = "op_RightShift";
			oper_names [(int) Operator.LessThan] = "op_LessThan";
			oper_names [(int) Operator.GreaterThan] = "op_GreaterThan";
			oper_names [(int) Operator.LessThanOrEqual] = "op_LessThanOrEqual";
			oper_names [(int) Operator.GreaterThanOrEqual] = "op_GreaterThanOrEqual";
			oper_names [(int) Operator.Equality] = "op_Equality";
			oper_names [(int) Operator.Inequality] = "op_Inequality";
			oper_names [(int) Operator.BitwiseAnd] = "op_BitwiseAnd";
			oper_names [(int) Operator.BitwiseOr] = "op_BitwiseOr";
			oper_names [(int) Operator.ExclusiveOr] = "op_ExclusiveOr";
			oper_names [(int) Operator.LogicalOr] = "op_LogicalOr";
			oper_names [(int) Operator.LogicalAnd] = "op_LogicalAnd";
			oper_names [(int) Operator.Is] = "op_Is";
		}

		public Binary (Operator oper, Expression left, Expression right, Location loc)
		{
			left = Parser.SetValueRequiredFlag (left);
			right = Parser.SetValueRequiredFlag (right);
			this.oper = oper;
			this.left = left;
			this.right = right;
			this.loc = loc;
		}

		public Operator Oper {
			get {
				return oper;
			}
			set {
				oper = value;
			}
		}
		
		public Expression Left {
			get {
				return left;
			}
			set {
				left = value;
			}
		}

		public Expression Right {
			get {
				return right;
			}
			set {
				right = value;
			}
		}


		/// <summary>
		///   Returns a stringified representation of the Operator
		/// </summary>
		static string OperName (Operator oper)
		{
			switch (oper){
			case Operator.Exponentiation:
				return "^";
			case Operator.Multiply:
				return "*";
			case Operator.Division:
				return "/";
			case Operator.IntDivision:
				return "\\";
			case Operator.Modulus:
				return "Mod";
			case Operator.Addition:
				return "+";
			case Operator.Subtraction:
				return "-";
			case Operator.LeftShift:
				return "<<";
			case Operator.RightShift:
				return ">>";
			case Operator.LessThan:
				return "<";
			case Operator.GreaterThan:
				return ">";
			case Operator.LessThanOrEqual:
				return "<=";
			case Operator.GreaterThanOrEqual:
				return ">=";
			case Operator.Equality:
				return "=";
			case Operator.Inequality:
				return "<>";
			case Operator.BitwiseAnd:
				return "And";
			case Operator.BitwiseOr:
				return "Or";
			case Operator.ExclusiveOr:
				return "^";
			case Operator.LogicalOr:
				return "Or";
			case Operator.LogicalAnd:
				return "And";
			case Operator.Is:
				return "Is";
			}

			return oper.ToString ();
		}

		public override string ToString ()
		{
			return "operator " + OperName (oper) + "(" + left.ToString () + ", " +
				right.ToString () + ")";
		}
		
		Expression ForceConversion (EmitContext ec, Expression expr, Type target_type)
		{
			if (expr.Type == target_type)
				return expr;

			return ConvertImplicit (ec, expr, target_type, Location.Null);
		}

		public static void Error_OperatorAmbiguous (Location loc, Operator oper, Type l, Type r)
		{
			Report.Error (
				34, loc, "Operator '" + OperName (oper) 
				+ "' is ambiguous on operands of type '"
				+ TypeManager.MonoBASIC_Name (l) + "' "
				+ "and '" + TypeManager.MonoBASIC_Name (r)
				+ "'");
		}

		//
		// Handles boolean types also
		//
		bool DoNumericPromotions (EmitContext ec, Type l, Type r, Operator oper)
		{

			Type conv_left_as = null;
			Type conv_right_as = null;
			if (left is NullLiteral)
				conv_left_as = r;
			if (right is NullLiteral)
				conv_right_as = l;

			// Need not do anything for shift operators, as this will be handled by the
			// 'CheckShiftArguments' method
			if (oper == Operator.LeftShift || oper == Operator.RightShift)
				return true;
			if (l == TypeManager.bool_type && r == TypeManager.bool_type) {
				if (IsArithmaticOperator (oper) && oper != Operator.Division) {
					type = TypeManager.int32_type;
					conv_left_as = conv_right_as = TypeManager.short_type;
				}
			}

			if (IsBitwiseOperator (oper)) {

				if (l == TypeManager.decimal_type || 
				    l == TypeManager.double_type ||
				    l == TypeManager.float_type) {
					conv_left_as = type = TypeManager.int64_type;
					l = conv_left_as;
				}
				if (r == TypeManager.decimal_type || 
				    r == TypeManager.double_type ||
				    r == TypeManager.float_type) {
					conv_right_as = type = TypeManager.int64_type;
					r = conv_right_as;
				}
			}

			if (oper == Operator.IntDivision) {
				if (l == TypeManager.decimal_type || r == TypeManager.decimal_type ||
				    l == TypeManager.float_type || r == TypeManager.float_type ||
				    l == TypeManager.double_type || r == TypeManager.double_type) 
					conv_left_as = conv_right_as = TypeManager.int64_type;
					l = r = TypeManager.int64_type;
			}

			if (IsLogicalOperator (oper)) {
				if (l == TypeManager.decimal_type)
					conv_left_as = TypeManager.bool_type;
				else if (r == TypeManager.decimal_type)
					conv_right_as = TypeManager.bool_type;
			} else if ((l == TypeManager.double_type || r == TypeManager.double_type) ||
				   (oper == Operator.Exponentiation) ||
			    	   (oper == Operator.Division && 
			    	   !(l == TypeManager.decimal_type || r == TypeManager.decimal_type))) {
				//
				// If either operand is of type double, the other operand is
				// conveted to type double.
				//
				type = conv_left_as = conv_right_as = TypeManager.double_type;
				
			} else if (l == TypeManager.float_type || r == TypeManager.float_type){
				//
				// if either operand is of type float, the other operand is
				// converted to type float.
				//
				type = conv_left_as = conv_right_as = TypeManager.float_type;
			} else if (l == TypeManager.decimal_type || r == TypeManager.decimal_type){
				type = conv_left_as = conv_right_as = TypeManager.decimal_type;
			} else if (l == TypeManager.int64_type || r == TypeManager.int64_type){
				//
				// If either operand is of type long, the other operand is converted
				// to type long.
				//
				type = conv_left_as = conv_right_as = TypeManager.int64_type;
			} else if (l == TypeManager.int32_type || r == TypeManager.int32_type){
				type = conv_left_as = conv_right_as = TypeManager.int32_type;
			} else if (l == TypeManager.short_type || r == TypeManager.short_type){
				conv_left_as = conv_right_as = TypeManager.short_type;
				type = TypeManager.int32_type;
			} else {
				type = TypeManager.int32_type;
			}

			if (conv_left_as != null)
				left = ConvertImplicit (ec, left, conv_left_as, loc);
			if (conv_right_as != null)
				right = ConvertImplicit (ec, right, conv_right_as, loc);

			return (left != null) && (right != null);
		}

		static public void Error_OperatorCannotBeApplied (Location loc, string name, Type l, Type r)
		{
			Report.Error (19, loc,
			       "Operator '" + name + "' cannot be applied to operands of type '" +
			       TypeManager.MonoBASIC_Name (l) + "' and '" +
			       TypeManager.MonoBASIC_Name (r) + "'");
		}
		
		void Error_OperatorCannotBeApplied ()
		{
			Error_OperatorCannotBeApplied (loc, OperName (oper), left.Type, right.Type);
		}

		static bool is_32_or_64 (Type t)
		{
			return (t == TypeManager.int32_type || t == TypeManager.uint32_type ||
				t == TypeManager.int64_type || t == TypeManager.uint64_type);
		}

		static bool is_unsigned (Type t)
		{
			return (t == TypeManager.uint32_type || t == TypeManager.uint64_type ||
				t == TypeManager.short_type || t == TypeManager.byte_type);
		}
					
		Expression CheckShiftArguments (EmitContext ec)
		{
			Expression e;

			e = ForceConversion (ec, right, TypeManager.int32_type);
			if (e == null){
				Error_OperatorCannotBeApplied ();
				return null;
			}

			type = left.Type;
			if (left is NullLiteral) {
				type = right.Type; 
				if (right.Type != TypeManager.bool_type) {
					left =  ConvertImplicit (ec, left, right.Type, loc);
					if (left == null) {
						Error_OperatorCannotBeApplied (loc, OperName (oper), left.Type, right.Type);
						return null;
					}
				}
			}
			right = e;

			if (type == TypeManager.bool_type) {
				left = ConvertImplicit (ec, left, TypeManager.short_type, loc);
				if (left == null) {
					Error_OperatorCannotBeApplied (loc, OperName (oper), left.Type, right.Type);
					return null;
				}
				type = left.Type;
			}

			int mask = 0;
			if ( type == TypeManager.byte_type)
				mask = 7;
			else if (type == TypeManager.short_type || type == TypeManager.bool_type)
				mask = 15;
			else if (type == TypeManager.int32_type || type == TypeManager.uint32_type)
				mask = 31;
			else 
				mask = 63;
			if (mask != 0) {
				right = new Binary (Binary.Operator.BitwiseAnd, right, new IntLiteral (mask), loc);
				right = right.DoResolve (ec);
			}

			if (type == TypeManager.byte_type || 
			    type == TypeManager.short_type ||
			    type == TypeManager.int32_type) {
				type = TypeManager.int32_type;
				return this;
			}

			if (type == TypeManager.int64_type)
				return this;
			if ((e = ConvertImplicit (ec, left, TypeManager.int64_type, loc)) != null) {
				left = e;
				type = TypeManager.int64_type;
				return this;
			}

			Error_OperatorCannotBeApplied ();
			return null;
		}

		bool IsRelationalOperator (Binary.Operator oper) {
			return (oper == Operator.Equality ||
				oper == Operator.Inequality ||	
				oper == Operator.LessThan ||	
				oper == Operator.LessThanOrEqual ||	
				oper == Operator.GreaterThan ||	
				oper == Operator.GreaterThanOrEqual);
		}

		bool IsArithmaticOperator (Binary.Operator oper) {
			return (oper == Operator.Addition ||
				oper == Operator.Subtraction ||	
				oper == Operator.Multiply ||	
				oper == Operator.Division ||	
				oper == Operator.IntDivision ||	
				oper == Operator.Exponentiation ||	
				oper == Operator.Modulus);
		}

		bool IsShiftOperator (Binary.Operator oper) {
			return (oper == Operator.LeftShift ||
				oper == Operator.RightShift);
		}

		bool IsLogicalOperator (Binary.Operator oper) {
			return (oper == Operator.LogicalOr ||
				oper == Operator.LogicalAnd);
		}

		bool IsBitwiseOperator (Binary.Operator oper) {
			return (oper == Operator.BitwiseOr ||
				oper == Operator.BitwiseAnd ||
				oper == Operator.ExclusiveOr);
		}

		Expression ResolveOperator (EmitContext ec)
		{
			Type l = left.Type;
			Type r = right.Type;

			Expression left_expr, right_expr;
			left_expr = right_expr = null;

			if (oper == Operator.Addition && right is Unary) {
				Unary unary_right = (Unary) right;
				if (unary_right.Oper == Unary.Operator.UnaryNegation) {
					oper = Operator.Subtraction;
					right = unary_right.Expr;
					r = right.Type;
				}
			}

			if (TypeManager.IsEnumType (l)) 
				l = TypeManager.EnumToUnderlying (l);
			if (TypeManager.IsEnumType (r)) 
				r = TypeManager.EnumToUnderlying (r);

			Type conv_left_as = null;
			Type conv_right_as = null;

			if (left is NullLiteral && (r.IsValueType || r == TypeManager.string_type)) {
				// Just treat nothing as the other type, implicit conversion 
				// will return the default value
				conv_left_as = r;
				l = r;
			}

			if (right is NullLiteral && (l.IsValueType || l == TypeManager.string_type)) {
				// Just treat nothing as the other type, implicit conversion 
				// will return the default value
				conv_right_as = l;
				r = l;
			}

			// deal with objects and reference types first
			if (l == TypeManager.object_type || r == TypeManager.object_type) {

	                        //
                                // operator != (object a, object b)
                                // operator == (object a, object b)
                                //
                                // For this to be used, both arguments have to be reference-types.
                                // Read the rationale on the spec (14.9.6)
                                //
                                // Also, if at compile time we know that the classes do not inherit
                                // one from the other, then we catch the error there.

				// If other type is a value type, convert it to object
				if (r == TypeManager.object_type &&
				    (l.IsValueType || l == TypeManager.string_type))
					left = ConvertImplicit (ec, left, TypeManager.object_type, loc);
				if (l == TypeManager.object_type &&
				    (r.IsValueType || r == TypeManager.string_type))
					right = ConvertImplicit (ec, right, TypeManager.object_type, loc);
				if (left == null || right == null) {
					Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
					return null;
				}

				l = left.Type;
				r = right.Type;

				if (l == TypeManager.object_type && r == TypeManager.object_type) {
					string fqn = null;
					switch (oper) {
					case Operator.Addition :
						fqn = "ObjectType.AddObj";
						break;
					case Operator.Subtraction :
						fqn = "ObjectType.SubObj";
						break;
					case Operator.Multiply :
						fqn = "ObjectType.MulObj";
						break;
					case Operator.Division :
						fqn = "ObjectType.DivObj";
						break;
					case Operator.IntDivision :
						fqn = "ObjectType.IDivObj";
						break;
					case Operator.Modulus :
						fqn = "ObjectType.ModObj";
						break;
					case Operator.Exponentiation :
						fqn = "ObjectType.PowObj";
						break;
					case Operator.Like :
						fqn = "ObjectType.LikeObj";
						break;
					case Operator.Equality :
					case Operator.Inequality :
					case Operator.LessThan :
					case Operator.LessThanOrEqual :
					case Operator.GreaterThan :
					case Operator.GreaterThanOrEqual :
						fqn = "ObjectType.ObjTst";
						break;
					case Operator.BitwiseAnd:
						fqn = "ObjectType.BitAndObj";
						break;
					case Operator.BitwiseOr:
						fqn = "ObjectType.BitOrObj";
						break;
					case Operator.ExclusiveOr:
						fqn = "ObjectType.BitXorObj";
						break;
					case Operator.LeftShift:
						fqn = "ObjectType.ShiftLeftObj";
						break;
					case Operator.RightShift:
						fqn = "ObjectType.ShiftRightObj";
						break;
					case Operator.Is:
						eclass = ExprClass.Value;
						type = TypeManager.bool_type;
						return this;
					}
			
					if (fqn == null) {
						Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
						return null;
					}

					if (oper == Operator.LeftShift || oper == Operator.RightShift) {
						right = ConvertImplicit (ec, right, TypeManager.object_type, loc);
						if (right == null) {
							Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
							return null;
						}
					}

					Expression etmp = Mono.MonoBASIC.Parser.DecomposeQI (
								"Microsoft.VisualBasic.CompilerServices." + fqn, 
								Location.Null);

					ArrayList args = new ArrayList ();
					args.Add (new Argument (left, Argument.AType.Expression));
					args.Add (new Argument (right, Argument.AType.Expression));
					if (IsRelationalOperator (oper)) 
						args.Add (new Argument (new BoolConstant (false), Argument.AType.Expression));
					if (oper == Operator.Like) 
						args.Add (new Argument(new IntLiteral (0), Argument.AType.Expression));
					Expression e = new Invocation (etmp, args, loc);
					if (IsRelationalOperator (oper)) {
						e = new Binary (oper, e.Resolve(ec), new IntConstant (0), loc);
					}
					return e.Resolve (ec);
				} else if (!l.IsValueType || !r.IsValueType) {

			 		// If one of the operands are reference types and other is object, support for 'Is' operator
                                	if (oper == Operator.Is) {
                                        	eclass = ExprClass.Value;
                                        	type = TypeManager.bool_type;
                                        	return this;
                                	}
				}

		
			} else if (!l.IsValueType || !r.IsValueType) {
				
				if (!l.IsValueType && !r.IsValueType) {
			 		// If both the operands are reference types, support for 'Is' operator
                                	if (oper == Operator.Is) {
                                       		eclass = ExprClass.Value;
                                        	type = TypeManager.bool_type;
                                        	return this;
                                	}
				}
				// Either of the operands are reference types
				if (l.IsSubclassOf (TypeManager.delegate_type) && 
				    r.IsSubclassOf (TypeManager.delegate_type)) {
					if (oper == Operator.Addition || oper == Operator.Subtraction) {
	                                        Arguments = new ArrayList ();
                                        	Arguments.Add (new Argument (left, Argument.AType.Expression));
                                        	Arguments.Add (new Argument (right, Argument.AType.Expression));
                                                                                                               
                                        	if (oper == Operator.Addition)
                                                	method = TypeManager.delegate_combine_delegate_delegate;
                                        	else
                                                	method = TypeManager.delegate_remove_delegate_delegate;
                                                                                                              	 
                                        	if (l != r) {
                                                	Error_OperatorCannotBeApplied ();
                                                	return null;
                                        	}
                                                                                                               
                                        	DelegateOperation = true;
                                        	type = l;
                                        	return this;
					}

					if (oper != Operator.Equality) {
						Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
						return null;
					}
				}

				bool left_is_string = (left.Type == TypeManager.string_type);
				bool right_is_string = (right.Type == TypeManager.string_type);

				if (left_is_string || right_is_string) {
	
					if (left is NullLiteral) {
						left_is_string = true;
						l = r;
					}
					if (right is NullLiteral) {
						right_is_string = true;
						r = l;
					}
					if (left_is_string && right_is_string) {
						if (oper == Operator.Addition) {
						// Both operands are string 
							Expression e = new StringConcat (loc, left, right);
							return e.Resolve(ec);
						}

						if (IsRelationalOperator (oper)) {
	
							Expression etmp = Mono.MonoBASIC.Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.StringType.StrCmp", Location.Null);
							eclass = ExprClass.Value;
							type = TypeManager.bool_type;
							ArrayList args = new ArrayList ();
							args.Add (new Argument(left, Argument.AType.Expression));
							args.Add (new Argument(right, Argument.AType.Expression));
							args.Add (new Argument(new BoolConstant(false), Argument.AType.Expression));
							Expression e = (Expression) new Invocation (etmp, args, loc);
							e = new Binary (oper, e.Resolve(ec), new IntConstant(0), loc);
							return e.Resolve(ec);
						}

						if (oper == Operator.Like) {
							Expression etmp = Mono.MonoBASIC.Parser.DecomposeQI ("Microsoft.VisualBasic.CompilerServices.StringType.StrLike", Location.Null);
							type = TypeManager.bool_type;
							ArrayList args = new ArrayList ();
							args.Add (new Argument(left, Argument.AType.Expression));
							args.Add (new Argument(right, Argument.AType.Expression));
							args.Add (new Argument(new IntLiteral (0), Argument.AType.Expression));
							Expression e = (Expression) new Invocation (etmp, args, loc);
							return e.Resolve (ec);
						}
					}

					Expression other = right_is_string ? left: right;
					Type other_type = other.Type;
	
					//
					// Disallow arithmatic / shift / logical operators on dates and characters
					//
					if (other_type == TypeManager.date_type || other_type == TypeManager.char_type) {
						if (!(oper == Operator.Addition || IsRelationalOperator (oper) || oper == Operator.Like)) {
							Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
							return null;
						}
					}
	
					if (oper == Operator.Addition) {
						if (other_type == TypeManager.void_type) {
							Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
							return null;
						}
						if (other_type == TypeManager.date_type || 
					    	other_type == TypeManager.char_type || 
					    	other_type == typeof (System.Char[])) {
							conv_left_as = conv_right_as = TypeManager.string_type;
							type = TypeManager.string_type;
						}  else {
							// numeric operand
							conv_right_as = conv_left_as = TypeManager.double_type;
							type = TypeManager.double_type;
						}
					} else if (IsRelationalOperator (oper)) {
						if (other_type == TypeManager.char_type || other_type == typeof (System.Char[])) {
							conv_left_as = conv_right_as = TypeManager.string_type;
						} else if (other_type == TypeManager.date_type) {
							conv_right_as = conv_left_as = other_type;
						} else if (other_type == TypeManager.bool_type) {
							conv_right_as = conv_left_as = other_type;
						} else if (! other_type.IsValueType) {
							// Do Nothing, just return
							type = TypeManager.bool_type;
							return this;
						} else {
							conv_right_as = conv_left_as = TypeManager.double_type;
						}
						type = TypeManager.bool_type;
	
					} else if (oper == Operator.Like) {
						conv_left_as = conv_right_as = TypeManager.string_type;
					} else if (oper == Operator.LeftShift || oper == Operator.RightShift) {
	
						conv_left_as = TypeManager.int64_type;
						conv_right_as = TypeManager.int32_type;
						type = TypeManager.int64_type;
	
					} else if ( IsLogicalOperator (oper)) {
						type = conv_right_as = conv_left_as = TypeManager.bool_type;
					} else if ( IsBitwiseOperator (oper)) {
	
				    		if (other_type == TypeManager.bool_type) {
							conv_right_as = conv_left_as = TypeManager.bool_type;
							type = TypeManager.bool_type;
						} else {
							conv_left_as = conv_right_as = TypeManager.int64_type;
							type = TypeManager.int64_type;
						}
					} else if (oper == Operator.Exponentiation) {
						conv_left_as = conv_right_as = TypeManager.double_type;
					} else if (oper == Operator.IntDivision) {
						conv_left_as = conv_right_as = TypeManager.int64_type;
					} else {
						// Arithmatic operators
						conv_right_as = conv_left_as = TypeManager.double_type;
						type = TypeManager.double_type;
					}
				} else {
					// Both are not of type string
					if (oper == Operator.Equality || oper == Operator.Inequality || oper == Operator.Is) {
						if (l.IsValueType || r.IsValueType) {
							Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
							return null;
						}
						type = TypeManager.bool_type;
						return this;
					} else {
						Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
						return null;
					}
				}
			} else if (l == TypeManager.date_type || r == TypeManager.date_type) {
				// Date with string operations handled above
				// Only other possiblity is date with date
				if (oper == Operator.Like) {
					conv_right_as = conv_left_as = TypeManager.string_type;
					type = TypeManager.bool_type;
				} else if (l == TypeManager.date_type && r == TypeManager.date_type) {
					if (oper == Operator.Addition) {
						conv_left_as = conv_right_as = TypeManager.string_type;
					} else if (IsRelationalOperator (oper)) { 
						Expression etmp = Mono.MonoBASIC.Parser.DecomposeQI ("System.DateTime.Compare", Location.Null);
						eclass = ExprClass.Value;
						type = TypeManager.bool_type;
						ArrayList args = new ArrayList ();
						args.Add (new Argument(left, Argument.AType.Expression));
						args.Add (new Argument(right, Argument.AType.Expression));
						Expression e = (Expression) new Invocation (etmp, args, loc);
						e = new Binary (oper, e.Resolve(ec), new IntConstant(0), loc);
						return e.Resolve(ec);
					} else {
						Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
						return null;
					}
				} else {
					Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
					return null;
				}
			} else if (l == TypeManager.char_type || r == TypeManager.char_type) {
				// char op string handled above
				if (oper == Operator.Like) {
					conv_right_as = conv_left_as = TypeManager.string_type;
					type = TypeManager.bool_type;
				} else if (l == TypeManager.char_type && r == TypeManager.char_type) {
					if (oper == Operator.Addition)
						conv_left_as = conv_right_as = TypeManager.string_type;
					else if (IsRelationalOperator (oper)) {
						type = TypeManager.bool_type;
					} else {
						Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
						return null;
					}
				} else {
					Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
					return null;
				}
			} else if (l.IsPointer || r.IsPointer) {
				if (oper == Operator.Addition || oper == Operator.Subtraction) {
					if (l.IsPointer){
						if (r.IsPointer && oper == Operator.Subtraction){
							if (r == l)
								return new PointerArithmetic (
									false, left, right, TypeManager.int64_type,
									loc);
					} else if (is_32_or_64 (r))
						return new PointerArithmetic (
							oper == Operator.Addition, left, right, l, loc);
					} else if (r.IsPointer && is_32_or_64 (l) && oper == Operator.Addition)
						return new PointerArithmetic (
							true, right, left, r, loc);
				}

				//
				// Pointer comparison
				//
				if (l.IsPointer && r.IsPointer){
					if (oper == Operator.Equality || oper == Operator.Inequality ||
					    oper == Operator.LessThan || oper == Operator.LessThanOrEqual ||
					    oper == Operator.GreaterThan || oper == Operator.GreaterThanOrEqual){
						type = TypeManager.bool_type;
						return this;
					}
				}
				Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
				return null;

			} else if (oper == Operator.Like) {
				conv_left_as = conv_right_as = TypeManager.string_type;
			} else {

				// Numeric Types
				DoNumericPromotions (ec, l, r, oper);
				if (left == null || right == null) {
					Error_OperatorCannotBeApplied (loc, OperName(oper), l, r);
					return null;
				}

				l = left.Type;
				r = right.Type;
				// Required conversions done by 'DoNumericPromotions' method
				// So Reset 'conv_left_as', 'conv_right_as'
				conv_left_as = conv_right_as = null;

				if (l == TypeManager.decimal_type  && r == TypeManager.decimal_type) {
					if (IsRelationalOperator (oper)) {
						Expression etmp = Mono.MonoBASIC.Parser.DecomposeQI ("System.Decimal.Compare", Location.Null);
						eclass = ExprClass.Value;
						type = TypeManager.bool_type;
						ArrayList args = new ArrayList ();
						args.Add (new Argument(left, Argument.AType.Expression));
						args.Add (new Argument(right, Argument.AType.Expression));
						Expression e = (Expression) new Invocation (etmp, args, loc);
						e = new Binary (oper, e.Resolve(ec), new IntConstant(0), loc);
						return e.Resolve(ec);
					} else if (IsArithmaticOperator (oper)) {
						string fqn = null;
						if (oper == Operator.Addition) 
							fqn = "System.Decimal.Add";
						else if (oper == Operator.Subtraction) 
							fqn = "System.Decimal.Subtract";
						else if (oper == Operator.Multiply) 
							fqn = "System.Decimal.Multiply";
						else if (oper == Operator.Division)
							fqn = "System.Decimal.Divide";
						else if (oper == Operator.Modulus) 
							fqn = "System.Decimal.Remainder";
						if (fqn != null) {

							Expression etmp = Mono.MonoBASIC.Parser.DecomposeQI (fqn, Location.Null);
							eclass = ExprClass.Value;
							type = TypeManager.decimal_type;
							ArrayList args = new ArrayList ();
							args.Add (new Argument(left, Argument.AType.Expression));
							args.Add (new Argument(right, Argument.AType.Expression));
							Expression e = (Expression) new Invocation (etmp, args, loc);
							return e.Resolve (ec);
						}
					}
				}
			}

			bool conv_done = false;
			if (conv_left_as != null && conv_left_as != l) {
				conv_done = true;
				left = ConvertImplicit (ec, left, conv_left_as, loc);
				if (left == null) {
					Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
					return null;
				}
				l = left.Type;
			}

			if (conv_right_as != null && conv_right_as != r) {
				conv_done = true;
				right = ConvertImplicit (ec, right, conv_right_as, loc);
				if (right == null) {
					Error_OperatorCannotBeApplied (loc, OperName (oper), l, r);
					return null;
				}
				r = right.Type;
			}

			if (conv_done) 
				return ResolveOperator (ec);


			if (oper == Operator.Exponentiation) {
				Expression etmp = Mono.MonoBASIC.Parser.DecomposeQI("System.Math.Pow", loc);
				ArrayList args = new ArrayList();
				args.Add (new Argument (left, Argument.AType.Expression));
				args.Add (new Argument (right, Argument.AType.Expression));
				Expression e = (Expression) new Invocation (etmp, args, loc);
				return e.Resolve(ec);
			}

			bool overload_failed = false;
			string op = oper_names [(int) oper];
			MethodGroupExpr union = null;
			left_expr = MemberLookup (ec, l, op, MemberTypes.Method, AllBindingFlags, loc);
			if (r != l) {
				right_expr = MemberLookup (
						ec, r, op, MemberTypes.Method, AllBindingFlags, loc);
				union = Invocation.MakeUnionSet (left_expr, right_expr, loc);
			} else 
				union = (MethodGroupExpr) left_expr;

			if (union != null) {
				Arguments = new ArrayList ();
				Arguments.Add (new Argument (left, Argument.AType.Expression));
				Arguments.Add (new Argument (right, Argument.AType.Expression));

				method = Invocation.OverloadResolve (ec, union, Arguments, Location.Null);
				if (method != null) {
					MethodInfo mi = (MethodInfo) method;

					type = mi.ReturnType;
					return this;
				} else {
					overload_failed = true;
				}
			}

			if (overload_failed) {
				Error_OperatorCannotBeApplied ();
				return null;
			}

			if (IsRelationalOperator (oper)) {
				type = TypeManager.bool_type;
				if (l == TypeManager.bool_type && r == TypeManager.bool_type) {
					// Reverse the operator - to make it consistent with vbc
					if (oper == Operator.LessThan) 
						oper = Operator.GreaterThan;
					else if (oper == Operator.GreaterThan)
						oper = Operator.LessThan;
					else if (oper == Operator.LessThanOrEqual)
						oper = Operator.GreaterThanOrEqual;
					else if (oper == Operator.GreaterThanOrEqual)
						oper = Operator.LessThanOrEqual;
				}
			}

			if (IsLogicalOperator (oper))
				type = TypeManager.bool_type;
			if (IsBitwiseOperator (oper)) {
				if (l == r) {
					if (l == TypeManager.byte_type ||
					    l == TypeManager.short_type ||
					    l == TypeManager.bool_type ||
					    l == TypeManager.int32_type ||
					    l == TypeManager.int64_type) 
						type = l;
					else {
						Error_OperatorCannotBeApplied();
						return null;
					}
				} else {
					Error_OperatorCannotBeApplied();
					return null;
				}
			}

			if (oper == Operator.LeftShift || oper == Operator.RightShift) {
				return CheckShiftArguments (ec);
			}

			return this;
		}
		

		public override Expression DoResolve (EmitContext ec)
		{
			left = left.Resolve (ec);
			right = right.Resolve (ec);

			if (left == null || right == null)
				return null;

			if (left.Type == null)
				throw new Exception (
					"Resolve returned non null, but did not set the type! (" +
					left + ") at Line: " + loc.Row);
			if (right.Type == null)
				throw new Exception (
					"Resolve returned non null, but did not set the type! (" +
					right + ") at Line: "+ loc.Row);

			eclass = ExprClass.Value;
			
			// To support  'Or' argument of AttributeTargets in AttributeUsage

			if (left is EnumConstant && oper != Operator.BitwiseOr) {
				left = ((EnumConstant) left).WidenToCompilerConstant();
			}

			if (right is EnumConstant && oper != Operator.BitwiseOr) {
				right = ((EnumConstant) right).WidenToCompilerConstant();
			}

			if (left is Constant && right is Constant){
				Expression e = ConstantFold.BinaryFold (
					ec, oper, (Constant) left, (Constant) right, loc);
				if (e != null)
					return e;
			}

			Expression etmp = ResolveOperator (ec);
			Type l = left.Type;
			
			// if the operands are of type byte/short, convert the result back to short/byte
			if (l == TypeManager.bool_type || l == TypeManager.short_type || l == TypeManager.byte_type) {
				if (l == TypeManager.bool_type)
					l = TypeManager.short_type;
				if (IsArithmaticOperator (oper) && oper != Operator.Division) {
					Expression conv_exp = ConvertImplicit (ec, etmp, l, loc);
					if (conv_exp != null)
						return conv_exp;
				} 
				if (IsShiftOperator (oper)) {
					// No overflow checks are needed
					if (l == TypeManager.byte_type)
						return new OpcodeCast (etmp, l, OpCodes.Conv_U1);
					else 
						return new OpcodeCast (etmp, l, OpCodes.Conv_I2);
				}
			}

			return etmp;
		}

		/// <remarks>
		///   EmitBranchable is called from Statement.EmitBoolExpression in the
		///   context of a conditional bool expression.  This function will return
		///   false if it is was possible to use EmitBranchable, or true if it was.
		///
		///   The expression's code is generated, and we will generate a branch to 'target'
		///   if the resulting expression value is equal to isTrue
		/// </remarks>
		public bool EmitBranchable (EmitContext ec, Label target, bool onTrue)
		{
			if (method != null)
				return false;

			ILGenerator ig = ec.ig;

			//
			// This is more complicated than it looks, but its just to avoid
			// duplicated tests: basically, we allow ==, !=, >, <, >= and <=
			// but on top of that we want for == and != to use a special path
			// if we are comparing against null
			//
			if (oper == Operator.Equality || oper == Operator.Inequality || oper == Operator.Is){
				bool my_on_true = oper == Operator.Inequality ? onTrue : !onTrue;
				
				if (left is NullLiteral){
					right.Emit (ec);
					if (my_on_true)
						ig.Emit (OpCodes.Brtrue, target);
					else
						ig.Emit (OpCodes.Brfalse, target);
					return true;
				} else if (right is NullLiteral){
					left.Emit (ec);
					if (my_on_true)
						ig.Emit (OpCodes.Brtrue, target);
					else
						ig.Emit (OpCodes.Brfalse, target);
					return true;
				} 
			} else if (!(oper == Operator.LessThan ||
				      oper == Operator.GreaterThan ||
				      oper == Operator.LessThanOrEqual ||
				      oper == Operator.GreaterThanOrEqual ||
				      oper == Operator.Is))
				return false;
			

			
			left.Emit (ec);
			right.Emit (ec);

			bool isUnsigned = is_unsigned (left.Type);

			switch (oper){
			case Operator.Equality:
				if (onTrue)
					ig.Emit (OpCodes.Beq, target);
				else
					ig.Emit (OpCodes.Bne_Un, target);
				break;

			case Operator.Inequality:
				if (onTrue)
					ig.Emit (OpCodes.Bne_Un, target);
				else
					ig.Emit (OpCodes.Beq, target);
				break;

			case Operator.LessThan:
				if (onTrue)
					if (isUnsigned)
						ig.Emit (OpCodes.Blt_Un, target);
					else
						ig.Emit (OpCodes.Blt, target);
				else
					if (isUnsigned)
						ig.Emit (OpCodes.Bge_Un, target);
					else
						ig.Emit (OpCodes.Bge, target);
				break;

			case Operator.GreaterThan:
				if (onTrue)
					if (isUnsigned)
						ig.Emit (OpCodes.Bgt_Un, target);
					else
						ig.Emit (OpCodes.Bgt, target);
				else
					if (isUnsigned)
						ig.Emit (OpCodes.Ble_Un, target);
					else
						ig.Emit (OpCodes.Ble, target);
				break;

			case Operator.LessThanOrEqual:
				if (onTrue)
					if (isUnsigned)
						ig.Emit (OpCodes.Ble_Un, target);
					else
						ig.Emit (OpCodes.Ble, target);
				else
					if (isUnsigned)
						ig.Emit (OpCodes.Bgt_Un, target);
					else
						ig.Emit (OpCodes.Bgt, target);
				break;


			case Operator.GreaterThanOrEqual:
				if (onTrue)
					if (isUnsigned)
						ig.Emit (OpCodes.Bge_Un, target);
					else
						ig.Emit (OpCodes.Bge, target);
				else
					if (isUnsigned)
						ig.Emit (OpCodes.Blt_Un, target);
					else
						ig.Emit (OpCodes.Blt, target);
				break;

			case Operator.Is:
				if (onTrue)
					ig.Emit (OpCodes.Beq, target); //Check this
				else
					ig.Emit (OpCodes.Bne_Un_S, target);
				break;

			default:
				return false;
			}
			
			return true;
		}
		
		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;
			Type l = left.Type;
			Type r = right.Type;
			//Type r = right.Type;
			OpCode opcode;

			if (method != null) {

				// Note that operators are static anyway
				
				if (Arguments != null) 
					Invocation.EmitArguments (ec, method, Arguments);
				
				if (method is MethodInfo)
					ig.Emit (OpCodes.Call, (MethodInfo) method);
				else
					ig.Emit (OpCodes.Call, (ConstructorInfo) method);

				if (DelegateOperation)
					ig.Emit (OpCodes.Castclass, type);
					
				return;
			}

			//
			// Handle short-circuit operators differently
			// than the rest
			//
			if (IsLogicalOperator (oper)) {
				Label load_zero = ig.DefineLabel ();
				Label load_one = ig.DefineLabel ();
				Label end = ig.DefineLabel ();
				
				left.Emit (ec);
				if (l != TypeManager.bool_type) {
					if (l == TypeManager.int64_type) {
						ec.ig.Emit (OpCodes.Ldc_I8, 0L);
						ec.ig.Emit (OpCodes.Cgt_Un);
					} else if (l == TypeManager.float_type) {
						ec.ig.Emit (OpCodes.Ldc_R4, 0.0F);
						ec.ig.Emit (OpCodes.Ceq);
						ec.ig.Emit (OpCodes.Ldc_I4_0);
						ec.ig.Emit (OpCodes.Ceq);
					} else if (l == TypeManager.double_type) {
						ec.ig.Emit (OpCodes.Ldc_R8, 0.0);
						ec.ig.Emit (OpCodes.Ceq);
						ec.ig.Emit (OpCodes.Ldc_I4_0);
						ec.ig.Emit (OpCodes.Ceq);
					} else  {
						ec.ig.Emit (OpCodes.Ldc_I4_0);
						ec.ig.Emit (OpCodes.Cgt_Un);
					}
				}
				if (oper == Operator.LogicalAnd) 
					ig.Emit (OpCodes.Brfalse, load_zero);
				else 
					ig.Emit (OpCodes.Brtrue, load_one);
				
				right.Emit (ec);
				if (r != TypeManager.bool_type) {
					if (r == TypeManager.int64_type) {
						ec.ig.Emit (OpCodes.Ldc_I8, 0L);
						ec.ig.Emit (OpCodes.Cgt_Un);
					} else if (r == TypeManager.float_type) {
						ec.ig.Emit (OpCodes.Ldc_R4, 0.0F);
						ec.ig.Emit (OpCodes.Ceq);
						ec.ig.Emit (OpCodes.Ldc_I4_0);
						ec.ig.Emit (OpCodes.Ceq);
					} else if (r == TypeManager.double_type) {
						ec.ig.Emit (OpCodes.Ldc_R8, 0.0);
						ec.ig.Emit (OpCodes.Ceq);
						ec.ig.Emit (OpCodes.Ldc_I4_0);
						ec.ig.Emit (OpCodes.Ceq);
					} else  {
						ec.ig.Emit (OpCodes.Ldc_I4_0);
						ec.ig.Emit (OpCodes.Cgt_Un);
					}
				}
				ig.Emit (OpCodes.Brtrue, load_one);
				ig.MarkLabel (load_zero);
				ig.Emit (OpCodes.Ldc_I4_0);
				ig.Emit (OpCodes.Br, end);
				ig.MarkLabel (load_one);
				ig.Emit (OpCodes.Ldc_I4_1);
				ig.MarkLabel (end);
				return;
			}
			
			left.Emit (ec);
			right.Emit (ec);

			switch (oper){
			case Operator.Multiply:
				if (ec.CheckState){
					if (l == TypeManager.int32_type || l == TypeManager.int64_type)
						opcode = OpCodes.Mul_Ovf;
					else if (l==TypeManager.uint32_type || l==TypeManager.uint64_type)
						opcode = OpCodes.Mul_Ovf_Un;
					else
						opcode = OpCodes.Mul;
				} else
					opcode = OpCodes.Mul;

				break;

			case Operator.Division:
			case Operator.IntDivision:
				if (l == TypeManager.uint32_type || l == TypeManager.uint64_type)
					opcode = OpCodes.Div_Un;
				else
					opcode = OpCodes.Div;
				break;

			case Operator.Modulus:
				if (l == TypeManager.uint32_type || l == TypeManager.uint64_type)
					opcode = OpCodes.Rem_Un;
				else
					opcode = OpCodes.Rem;
				break;

			case Operator.Addition:
				if (ec.CheckState){
					if (l == TypeManager.int32_type || l == TypeManager.int64_type)
						opcode = OpCodes.Add_Ovf;
					else if (l==TypeManager.uint32_type || l==TypeManager.uint64_type)
						opcode = OpCodes.Add_Ovf_Un;
					else
						opcode = OpCodes.Add;
				} else
					opcode = OpCodes.Add;
				break;

			case Operator.Subtraction:
				if (ec.CheckState){
					if (l == TypeManager.int32_type || l == TypeManager.int64_type)
						opcode = OpCodes.Sub_Ovf;
					else if (l==TypeManager.uint32_type || l==TypeManager.uint64_type)
						opcode = OpCodes.Sub_Ovf_Un;
					else
						opcode = OpCodes.Sub;
				} else
					opcode = OpCodes.Sub;
				break;

			case Operator.RightShift:
				if (l == TypeManager.uint32_type || l == TypeManager.uint64_type)
					opcode = OpCodes.Shr_Un;
				else
					opcode = OpCodes.Shr;
				break;
				
			case Operator.LeftShift:
				opcode = OpCodes.Shl;
				break;

			case Operator.Equality:
			case Operator.Is:
				opcode = OpCodes.Ceq;
				break;

			case Operator.Inequality:
				ec.ig.Emit (OpCodes.Ceq);
				ec.ig.Emit (OpCodes.Ldc_I4_0);
				
				opcode = OpCodes.Ceq;
				break;

			case Operator.LessThan:
				opcode = OpCodes.Clt;
				break;

			case Operator.GreaterThan:
				opcode = OpCodes.Cgt;
				break;

			case Operator.LessThanOrEqual:
				ec.ig.Emit (OpCodes.Cgt);
				ec.ig.Emit (OpCodes.Ldc_I4_0);
				
				opcode = OpCodes.Ceq;
				break;

			case Operator.GreaterThanOrEqual:
				ec.ig.Emit (OpCodes.Clt);
				ec.ig.Emit (OpCodes.Ldc_I4_1);
				
				opcode = OpCodes.Sub;
				break;

			case Operator.BitwiseOr:
				opcode = OpCodes.Or;
				break;

			case Operator.BitwiseAnd:
				opcode = OpCodes.And;
				break;

			case Operator.ExclusiveOr:
				opcode = OpCodes.Xor;
				break;

			default:
				throw new Exception ("This should not happen: Operator = "
						     + oper.ToString ());
			}

			ig.Emit (opcode);
		}

		public bool IsBuiltinOperator {
			get {
				return method == null;
			}
		}
	}

	public class PointerArithmetic : Expression {
		Expression left, right;
		bool is_add;

		//
		// We assume that 'l' is always a pointer
		//
		public PointerArithmetic (bool is_addition, Expression l, Expression r, Type t,
					  Location loc)
		{
			type = t;
			eclass = ExprClass.Variable;
			this.loc = loc;
			left = l;
			right = r;
			is_add = is_addition;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			//
			// We are born fully resolved
			//
			return this;
		}

		public override void Emit (EmitContext ec)
		{
			Type op_type = left.Type;
			ILGenerator ig = ec.ig;
			int size = GetTypeSize (op_type.GetElementType ());
			
			if (right.Type.IsPointer){
				//
				// handle (pointer - pointer)
				//
				left.Emit (ec);
				right.Emit (ec);
				ig.Emit (OpCodes.Sub);

				if (size != 1){
					if (size == 0)
						ig.Emit (OpCodes.Sizeof, op_type);
					else 
						IntLiteral.EmitInt (ig, size);
					ig.Emit (OpCodes.Div);
				}
				ig.Emit (OpCodes.Conv_I8);
			} else {
				//
				// handle + and - on (pointer op int)
				//
				left.Emit (ec);
				ig.Emit (OpCodes.Conv_I);
				right.Emit (ec);
				if (size != 1){
					if (size == 0)
						ig.Emit (OpCodes.Sizeof, op_type);
					else 
						IntLiteral.EmitInt (ig, size);
					ig.Emit (OpCodes.Mul);
				}
				if (is_add)
					ig.Emit (OpCodes.Add);
				else
					ig.Emit (OpCodes.Sub);
			}
		}
	}
	
	/// <summary>
	///   Implements the ternary conditional operator (?:)
	/// </summary>
	public class Conditional : Expression {
		Expression expr, trueExpr, falseExpr;
		
		public Conditional (Expression expr, Expression trueExpr, Expression falseExpr, Location l)
		{
			this.expr = expr;
			this.trueExpr = trueExpr;
			this.falseExpr = falseExpr;
			this.loc = l;
		}

		public Expression Expr {
			get {
				return expr;
			}
		}

		public Expression TrueExpr {
			get {
				return trueExpr;
			}
		}

		public Expression FalseExpr {
			get {
				return falseExpr;
			}
		}

		public override Expression DoResolve (EmitContext ec)
		{
			expr = expr.Resolve (ec);

			if (expr == null)
				return null;
			
			if (expr.Type != TypeManager.bool_type)
				expr = Expression.ConvertImplicitRequired (
					ec, expr, TypeManager.bool_type, loc);
			
			trueExpr = trueExpr.Resolve (ec);
			falseExpr = falseExpr.Resolve (ec);

			if (trueExpr == null || falseExpr == null)
				return null;

			eclass = ExprClass.Value;
			if (trueExpr.Type == falseExpr.Type)
				type = trueExpr.Type;
			else {
				Expression conv;
				Type true_type = trueExpr.Type;
				Type false_type = falseExpr.Type;

				if (trueExpr is NullLiteral){
					type = false_type;
					return this;
				} else if (falseExpr is NullLiteral){
					type = true_type;
					return this;
				}
				
				//
				// First, if an implicit conversion exists from trueExpr
				// to falseExpr, then the result type is of type falseExpr.Type
				//
				conv = ConvertImplicit (ec, trueExpr, false_type, loc);
				if (conv != null){
					//
					// Check if both can convert implicitl to each other's type
					//
					if (ConvertImplicit (ec, falseExpr, true_type, loc) != null){
						Error (172,
						       "Can not compute type of conditional expression " +
						       "as '" + TypeManager.MonoBASIC_Name (trueExpr.Type) +
						       "' and '" + TypeManager.MonoBASIC_Name (falseExpr.Type) +
						       "' convert implicitly to each other");
						return null;
					}
					type = false_type;
					trueExpr = conv;
				} else if ((conv = ConvertImplicit(ec, falseExpr, true_type,loc))!= null){
					type = true_type;
					falseExpr = conv;
				} else {
					Error (173, "The type of the conditional expression can " +
					       "not be computed because there is no implicit conversion" +
					       " from '" + TypeManager.MonoBASIC_Name (trueExpr.Type) + "'" +
					       " and '" + TypeManager.MonoBASIC_Name (falseExpr.Type) + "'");
					return null;
				}
			}

			if (expr is BoolConstant){
				BoolConstant bc = (BoolConstant) expr;

				if (bc.Value)
					return trueExpr;
				else
					return falseExpr;
			}

			return this;
		}

		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;
			Label false_target = ig.DefineLabel ();
			Label end_target = ig.DefineLabel ();

			Statement.EmitBoolExpression (ec, expr, false_target, false);
			trueExpr.Emit (ec);
			ig.Emit (OpCodes.Br, end_target);
			ig.MarkLabel (false_target);
			falseExpr.Emit (ec);
			ig.MarkLabel (end_target);
		}

	}

	/// <summary>
	///   Local variables
	/// </summary>
	public class LocalVariableReference : Expression, IAssignMethod, IMemoryLocation, IVariable {
		public readonly string Name;
		public readonly Block Block;
		VariableInfo variable_info;
		bool is_readonly;
		
		public LocalVariableReference (Block block, string name, Location l)
		{
			Block = block;
			Name = name;
			loc = l;
			eclass = ExprClass.Variable;
		}

		// Setting 'is_readonly' to false will allow you to create a writable
		// reference to a read-only variable.  This is used by foreach and using.
		public LocalVariableReference (Block block, string name, Location l,
					       VariableInfo variable_info, bool is_readonly)
			: this (block, name, l)
		{
			this.variable_info = variable_info;
			this.is_readonly = is_readonly;
		}

		public VariableInfo VariableInfo {
			get {
				if (variable_info == null) {
					variable_info = Block.GetVariableInfo (Name);
					is_readonly = variable_info.ReadOnly;
				}
				return variable_info;
			}
		}

		public bool IsAssigned (EmitContext ec, Location loc)
		{
			return VariableInfo.IsAssigned (ec, loc);
		}

		public bool IsFieldAssigned (EmitContext ec, string name, Location loc)
		{
			return VariableInfo.IsFieldAssigned (ec, name, loc);
		}

		public void SetAssigned (EmitContext ec)
		{
			VariableInfo.SetAssigned (ec);
		}

		public void SetFieldAssigned (EmitContext ec, string name)
		{
			VariableInfo.SetFieldAssigned (ec, name);
		}

		public bool IsReadOnly {
			get {
				if (variable_info == null) {
					variable_info = Block.GetVariableInfo (Name);
					is_readonly = variable_info.ReadOnly;
				}
				return is_readonly;
			}
		}
		
		public override Expression DoResolve (EmitContext ec)
		{
			VariableInfo vi = VariableInfo;

			if (Block.IsConstant (Name)) {
				Expression e = Block.GetConstantExpression (Name);

				vi.Used = true;
				return e;
			}

			if (ec.DoFlowAnalysis && !IsAssigned (ec, loc))
				return null;

			type = vi.VariableType;
			return this;
		}

		override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
		{
			VariableInfo vi = VariableInfo;

			if (ec.DoFlowAnalysis)
				ec.SetVariableAssigned (vi);

			Expression e = DoResolve (ec);

			if (e == null)
				return null;

			if (is_readonly){
				Error (1604, "cannot assign to '" + Name + "' because it is readonly");
				return null;
			}
			
			return this;
		}

		public override void Emit (EmitContext ec)
		{
			VariableInfo vi = VariableInfo;
			ILGenerator ig = ec.ig;

			ig.Emit (OpCodes.Ldloc, vi.LocalBuilder);
			vi.Used = true;
		}
		
		public void EmitAssign (EmitContext ec, Expression source)
		{
			ILGenerator ig = ec.ig;
			VariableInfo vi = VariableInfo;

			vi.Assigned = true;

			source.Emit (ec);
			
			ig.Emit (OpCodes.Stloc, vi.LocalBuilder);
		}
		
		public void AddressOf (EmitContext ec, AddressOp mode)
		{
			VariableInfo vi = VariableInfo;

			ec.ig.Emit (OpCodes.Ldloca, vi.LocalBuilder);
		}
	}

	/// <summary>
	///   This represents a reference to a parameter in the intermediate
	///   representation.
	/// </summary>
	public class ParameterReference : Expression, IAssignMethod, IMemoryLocation, IVariable {
		Parameters pars;
		String name;
		int idx;
		public Parameter.Modifier mod;
		public bool is_ref, is_out;
		
		public ParameterReference (Parameters pars, int idx, string name, Location loc)
		{
			this.pars = pars;
			this.idx  = idx;
			this.name = name;
			this.loc = loc;
			eclass = ExprClass.Variable;
		}

		public bool IsAssigned (EmitContext ec, Location loc)
		{
			if (!is_out || !ec.DoFlowAnalysis)
				return true;

			if (!ec.CurrentBranching.IsParameterAssigned (idx)) {
				Report.Error (165, loc,
					      "Use of unassigned local variable '" + name + "'");
				return false;
			}

			return true;
		}

		public bool IsFieldAssigned (EmitContext ec, string field_name, Location loc)
		{
			if (!is_out || !ec.DoFlowAnalysis)
				return true;

			if (ec.CurrentBranching.IsParameterAssigned (idx))
				return true;

			if (!ec.CurrentBranching.IsParameterAssigned (idx, field_name)) {
				Report.Error (170, loc,
					      "Use of possibly unassigned field '" + field_name + "'");
				return false;
			}

			return true;
		}

		public void SetAssigned (EmitContext ec)
		{
			if (is_out && ec.DoFlowAnalysis)
				ec.CurrentBranching.SetParameterAssigned (idx);
		}

		public void SetFieldAssigned (EmitContext ec, string field_name)
		{
			if (is_out && ec.DoFlowAnalysis)
				ec.CurrentBranching.SetParameterAssigned (idx, field_name);
		}

		//
		// Notice that for ref/out parameters, the type exposed is not the
		// same type exposed externally.
		//
		// for "ref int a":
		//   externally we expose "int&"
		//   here we expose       "int".
		//
		// We record this in "is_ref".  This means that the type system can treat
		// the type as it is expected, but when we generate the code, we generate
		// the alternate kind of code.
		//
		public override Expression DoResolve (EmitContext ec)
		{
			type = pars.GetParameterInfo (ec.DeclSpace, idx, out mod);
			is_ref = (mod & Parameter.Modifier.ISBYREF) != 0;
			// is_out = (mod & Parameter.Modifier.OUT) != 0;
			eclass = ExprClass.Variable;

			/*  if (is_out && ec.DoFlowAnalysis && !IsAssigned (ec, loc))
				return null;
			*/
			return this;
		}

		override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
		{
			type = pars.GetParameterInfo (ec.DeclSpace, idx, out mod);
			is_ref = (mod & Parameter.Modifier.ISBYREF) != 0;
			// is_out = (mod & Parameter.Modifier.OUT) != 0;
			eclass = ExprClass.Variable;
			/*
			if (is_out && ec.DoFlowAnalysis)
				ec.SetParameterAssigned (idx);
			*/
			return this;
		}

		static void EmitLdArg (ILGenerator ig, int x)
		{
			if (x <= 255){
				switch (x){
				case 0: ig.Emit (OpCodes.Ldarg_0); break;
				case 1: ig.Emit (OpCodes.Ldarg_1); break;
				case 2: ig.Emit (OpCodes.Ldarg_2); break;
				case 3: ig.Emit (OpCodes.Ldarg_3); break;
				default: ig.Emit (OpCodes.Ldarg_S, (byte) x); break;
				}
			} else
				ig.Emit (OpCodes.Ldarg, x);
		}
		
		//
		// This method is used by parameters that are references, that are
		// being passed as references:  we only want to pass the pointer (that
		// is already stored in the parameter, not the address of the pointer,
		// and not the value of the variable).
		//
		public void EmitLoad (EmitContext ec)
		{
			ILGenerator ig = ec.ig;
			int arg_idx = idx;

			if (!ec.IsStatic)
				arg_idx++;

			EmitLdArg (ig, arg_idx);
		}
		
		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;
			int arg_idx = idx;

			if (!ec.IsStatic)
				arg_idx++;

			EmitLdArg (ig, arg_idx);

			if (!is_ref)
				return;

			//
			// If we are a reference, we loaded on the stack a pointer
			// Now lets load the real value
			//
			LoadFromPtr (ig, type);
		}

		public void EmitAssign (EmitContext ec, Expression source)
		{
			ILGenerator ig = ec.ig;
			int arg_idx = idx;

			if (!ec.IsStatic)
				arg_idx++;

			if (is_ref)
				EmitLdArg (ig, arg_idx);
			
			source.Emit (ec);

			if (is_ref)
				StoreFromPtr (ig, type);
			else {
				if (arg_idx <= 255)
					ig.Emit (OpCodes.Starg_S, (byte) arg_idx);
				else
					ig.Emit (OpCodes.Starg, arg_idx);
			}
		}

		public void AddressOf (EmitContext ec, AddressOp mode)
		{
			int arg_idx = idx;

			if (!ec.IsStatic)
				arg_idx++;

			if (is_ref){
				if (arg_idx <= 255)
					ec.ig.Emit (OpCodes.Ldarg_S, (byte) arg_idx);
				else
					ec.ig.Emit (OpCodes.Ldarg, arg_idx);
			} else {
				if (arg_idx <= 255)
					ec.ig.Emit (OpCodes.Ldarga_S, (byte) arg_idx);
				else
					ec.ig.Emit (OpCodes.Ldarga, arg_idx);
			}
		}
	}
	
	
	/// <summary>
	///   Invocation of methods or delegates.
	/// </summary>
	public class Invocation : ExpressionStatement {
		public ArrayList Arguments;

		public Expression expr;
		MethodBase method = null;
		bool is_base;
		bool is_latebinding;
		bool is_left_hand; // Needed for late bound calls
		bool is_retval_required; // Needed for late bound calls
		static Hashtable method_parameter_cache;
		//static MemberFilter CompareName;

		static ArrayList tempvars; // For ByRef - different parameter and argument type
		static bool is_byref_conversion = false; //For ByRef when it is converted 
		static string errorMsg = "";

		static Invocation ()
		{
			method_parameter_cache = new PtrHashtable ();
		}
			
		//
		// arguments is an ArrayList, but we do not want to typecast,
		// as it might be null.
		//
		// FIXME: only allow expr to be a method invocation or a
		// delegate invocation (7.5.5)
		//
		public Invocation (Expression expr, ArrayList arguments, Location l)
		{
			this.expr = expr;
			if (this.expr is MemberAccess) {
				((MemberAccess) this.expr).IsInvocation = true;
			}
			this.is_retval_required = false;
			this.is_left_hand = false;
			Arguments = arguments;
			loc = l;
			//CompareName = new MemberFilter (compare_name_filter);
		}

		public Expression Expr {
			get {
				return expr;
			}
		}

		public bool IsLeftHand {
			get {
				return is_left_hand;
			}
			set {
				is_left_hand = value;
			}
		}

		public bool IsRetvalRequired {
			get {
				return is_retval_required;
			}
			set {
				is_retval_required = value;
			}
		}

		public bool IsLateBinding {
			get {
				return is_latebinding;
			}
			set {
				is_latebinding = value;
			}
		}

		/// <summary>
		///   Returns the Parameters (a ParameterData interface) for the
		///   Method 'mb'
		/// </summary>
		public static ParameterData GetParameterData (MethodBase mb)
		{
			object pd = method_parameter_cache [mb];
			object ip;
			
			if (pd != null)
				return (ParameterData) pd;

			
			ip = TypeManager.LookupParametersByBuilder (mb);
			if (ip != null){
				method_parameter_cache [mb] = ip;

				return (ParameterData) ip;
			} else {
				ParameterInfo [] pi = mb.GetParameters ();

				ReflectionParameters rp = new ReflectionParameters (pi);
				method_parameter_cache [mb] = rp;

				return (ParameterData) rp;
			}
		}

		enum Applicability { Same, Better, Worse };

		/// <summary>
		///  Determines "Better function"
		/// </summary>
		/// <remarks>
		///    and returns an integer indicating :
		///    0 if candidate ain't better
		///    1 if candidate is better than the current best match
		/// </remarks>
		static Applicability BetterFunction (EmitContext ec, ArrayList args,
					    MethodBase candidate, MethodBase best,
					    bool expanded_form, Location loc)
		{
			ParameterData candidate_pd = GetParameterData (candidate);
			ParameterData best_pd;
			int argument_count;

			if (args == null)
				argument_count = 0;
			else
				argument_count = args.Count;

			int cand_count = candidate_pd.Count;

			if (cand_count == 0 && argument_count == 0)
				return Applicability.Same;

			if (candidate_pd.ParameterModifier (cand_count - 1) != Parameter.Modifier.PARAMS)
				if (cand_count != argument_count)
					return Applicability.Worse;
			
			best_pd = GetParameterData (best);

			Applicability res = Applicability.Same;

			for (int j = 0; j < argument_count; ++j) {
				
				//Argument a = (Argument) args [j];

				Type ct = candidate_pd.ParameterType (j);
				Type bt = best_pd.ParameterType (j);

				if (candidate_pd.ParameterModifier (j) == Parameter.Modifier.PARAMS)
					if (expanded_form)
						ct = ct.GetElementType ();

				if (best_pd.ParameterModifier (j) == Parameter.Modifier.PARAMS)
					if (expanded_form)
						bt = bt.GetElementType ();
				
				if (ct != bt) {
					if (!WideningConversionExists (ct, bt))
						return Applicability.Worse;
					res = Applicability.Better;
				}
			}

			if (res == Applicability.Same)
				if (candidate_pd.Count < best_pd.Count)
					res = Applicability.Better;
				else if (candidate_pd.Count > best_pd.Count)
					res = Applicability.Worse;

			return res;
		}

		public static string FullMethodDesc (MethodBase mb)
		{
			string ret_type = "";

			if (mb is MethodInfo)
				ret_type = TypeManager.MonoBASIC_Name (((MethodInfo) mb).ReturnType) + " ";
			
			StringBuilder sb = new StringBuilder (ret_type + mb.Name);
			ParameterData pd = GetParameterData (mb);

			int count = pd.Count;
			sb.Append (" (");
			
			for (int i = count; i > 0; ) {
				i--;

				sb.Append (pd.ParameterDesc (count - i - 1));
				if (i != 0)
					sb.Append (", ");
			}
			
			sb.Append (")");
			return sb.ToString ();
		}

		public static MethodGroupExpr MakeUnionSet (Expression mg1, Expression mg2, Location loc)
		{
			MemberInfo [] miset;
			MethodGroupExpr union;

			if (mg1 == null){
				if (mg2 == null)
					return null;
				return (MethodGroupExpr) mg2;
			} else {
				if (mg2 == null)
					return (MethodGroupExpr) mg1;
			}
			
			MethodGroupExpr left_set = null, right_set = null;
			int length1 = 0, length2 = 0;
			
			left_set = (MethodGroupExpr) mg1;
			length1 = left_set.Methods.Length;
			
			right_set = (MethodGroupExpr) mg2;
			length2 = right_set.Methods.Length;
			
			ArrayList common = new ArrayList ();

			foreach (MethodBase l in left_set.Methods){
				foreach (MethodBase r in right_set.Methods){
					if (l != r)
						continue;
					common.Add (r);
					break;
				}
			}
			
			miset = new MemberInfo [length1 + length2 - common.Count];
			left_set.Methods.CopyTo (miset, 0);
			
			int k = length1;

			foreach (MemberInfo mi in right_set.Methods){
				if (!common.Contains (mi))
					miset [k++] = mi;
			}
			
			union = new MethodGroupExpr (miset, loc);
			
			return union;
		}


		protected enum ConversionType { None, Widening, Narrowing };

		static ConversionType CheckParameterAgainstArgument (EmitContext ec, ParameterData pd, int i, Argument a, Type ptype)
		{
                       if (a.ArgType == Argument.AType.NoArg)  {
                               return ConversionType.Widening;
                       }

			Parameter.Modifier a_mod = a.GetParameterModifier () &
				~(Parameter.Modifier.REF);
			Parameter.Modifier p_mod = pd.ParameterModifier (i) &
				~(Parameter.Modifier.REF | Parameter.Modifier.OPTIONAL);

			if (a_mod == p_mod ||
				(a_mod == Parameter.Modifier.NONE && p_mod == Parameter.Modifier.PARAMS)) {
				// if (a_mod == Parameter.Modifier.NONE) {
					if (! WideningConversionExists (a.Expr, ptype) ) {

						if (! NarrowingConversionExists (ec, a.Expr, ptype) )
							return ConversionType.None;
						else
							return ConversionType.Narrowing;
					} else
						return ConversionType.Widening;
				 // }
				
/*
				if ((a_mod & Parameter.Modifier.ISBYREF) != 0) {
					Type pt = pd.ParameterType (i);
					
					if (!pt.IsByRef)
						pt = TypeManager.LookupType (pt.FullName + "&");

					if (pt != a.Type)
						return ConversionType.None;
				}
				return ConversionType.Widening;
*/
			} else
				return ConversionType.None;					
		}

		static bool HasArrayParameter (ParameterData pd)
		{
			int c = pd.Count;
			return c > 0 && (pd.ParameterModifier (c - 1) & Parameter.Modifier.PARAMS) != 0;
		}

		static int CountStandardParams (ParameterData pd) 
		{
			int count = pd.Count;
			for (int i = 0; i < count; i++) {
				Parameter.Modifier pm = pd.ParameterModifier (i);
				if ((pm & (Parameter.Modifier.OPTIONAL | Parameter.Modifier.PARAMS)) != 0)
					return i;
			}
			return count;
		}

		static ConversionType IsApplicable (EmitContext ec, ArrayList arguments, MethodBase candidate,
						    out bool expanded)
		{
			bool objectArgsPresent;
			return IsApplicable (ec, arguments, candidate, out expanded, out objectArgsPresent);
		}

		/// <summary>
		///  Determines if the candidate method is applicable (section 14.4.2.1)
		///  to the given set of arguments
		/// </summary>
		static ConversionType IsApplicable (EmitContext ec, ArrayList arguments, MethodBase candidate,
						    out bool expanded, out bool objectArgsPresent)
		{
			int arg_count;
			Type param_type;

			expanded = objectArgsPresent = false;
			int num_narr_conv = 0;		// Count the narrowing conversion not involving object
							// arguments
			
			if (arguments == null)
				arg_count = 0;
			else
				arg_count = arguments.Count;

			ParameterData pd = GetParameterData (candidate);
			int ps_count = CountStandardParams (pd);			
			int pd_count = pd.Count;

			// Validate argument count
			if (ps_count == pd_count) {
				if (arg_count != pd_count)
					return ConversionType.None;
			}
			else {
				if (arg_count < ps_count)
					return ConversionType.None;
				if (!HasArrayParameter (pd) && arg_count > pd_count)
					return ConversionType.None;
			}       

			ConversionType result = ConversionType.Widening;
			if (arg_count > 0) {
				result = ConversionType.None;
				int array_param_index = -1;
				for (int i = 0; i < arg_count; ++i) {
					Argument a = (Argument) arguments [i];
					param_type = pd.ParameterType (i);
					Parameter.Modifier mod = pd.ParameterModifier (i);
					if (array_param_index < 0 && (mod & Parameter.Modifier.PARAMS) != 0)
						array_param_index = i;

					bool IsDelegate = TypeManager.IsDelegateType (param_type);

					if (IsDelegate)	{	
						if (a.ArgType == Argument.AType.AddressOf) {
							a = new Argument ((Expression) a.Expr, Argument.AType.Expression);
							ArrayList args = new ArrayList();
							args.Add (a);
							string param_name = pd.ParameterDesc(i).Replace('+', '.');
							Expression pname = MonoBASIC.Parser.DecomposeQI (param_name, Location.Null);

							New temp_new = new New ((Expression)pname, args, Location.Null);
							Expression del_temp = temp_new.DoResolve(ec);

							if (del_temp == null)
								return ConversionType.None;

							a = new Argument (del_temp, Argument.AType.Expression);
							if (!a.Resolve(ec, Location.Null))
								return ConversionType.None;
						}
					}
					else {
						if (a.ArgType == Argument.AType.AddressOf)
							return ConversionType.None;
					}

					if (a.ArgType != Argument.AType.NoArg && (mod & Parameter.Modifier.REF) != 0) {
						a = new Argument (a.Expr, Argument.AType.Ref);
						if (!a.Resolve(ec,Location.Null))
							return ConversionType.None;
					}

					ConversionType match = ConversionType.None;
					if (i == array_param_index) 
						match = CheckParameterAgainstArgument (ec, pd, i, a, param_type);
					if (match == ConversionType.None && array_param_index >= 0 && i >= array_param_index) {
						expanded = true;
						param_type = param_type.GetElementType ();
					}
					if (match == ConversionType.None)
						match = CheckParameterAgainstArgument (ec, pd, i, a, param_type);
					if (match == ConversionType.None)
						return ConversionType.None;

					if (match == ConversionType.Narrowing) {
						result = match;
						if (a.Expr.Type == TypeManager.object_type)
							objectArgsPresent = true;
						else {
							objectArgsPresent = false;
							num_narr_conv ++;
						}
					} else if (result == ConversionType.None)
						result = match;
				}
			}

			if (num_narr_conv > 0)	// There were narrowing conversions other than those for object arguments
				objectArgsPresent = false;

			return result;
		}

		internal static ArrayList ReorderArguments (MethodBase mb,
							    ArrayList Arguments,
							    CaseInsensitiveHashtable namedArgs,
							    ref string ErrMsg,
							    Location loc)
		{
			ArrayList orderedArgs = new ArrayList ();
			ParameterData pd = GetParameterData (mb);
			bool error = false;
			for (int index = 0; index < pd.Count; index ++) {
				string paramName = pd.ParameterName (index);
				if (namedArgs.Contains (paramName)) {
					if ((pd.ParameterModifier (index) & Parameter.Modifier.PARAMS) == Parameter.Modifier.PARAMS) {
						error = true;
						ErrMsg += "\n\t'" + FullMethodDesc (mb) + "': Named argument cannot match a ParamArray parameter";
						continue;
					}
					int argIndex = (int) namedArgs [paramName];
					orderedArgs.Add (Arguments [argIndex]);
				} else {
					Parameter.Modifier p_mod = pd.ParameterModifier (index) & Parameter.Modifier.OPTIONAL;
					if (p_mod == Parameter.Modifier.OPTIONAL)
						orderedArgs.Add (new Argument (pd.ParameterName (index), new EmptyExpression (), Argument.AType.NoArg));
					 else {
						error = true;
						ErrMsg += "\n\t'" + FullMethodDesc (mb) + "': Argument not specified for parameter '" + paramName + "'";
					}
				}
			}

			if (Arguments.Count > orderedArgs.Count) {
				for (int argIndex = 0; argIndex < Arguments.Count; argIndex ++) {
					string argName = ((Argument) Arguments [argIndex]).ParamName;
					bool found = false;
					for (int paramIndex = 0; paramIndex < pd.Count; paramIndex ++) {
						string paramName = pd.ParameterName (paramIndex);
						if (String.Compare (argName, paramName, true) == 0) {
							found = true;
							break;
						}
					}
					if (!found) {
						error = true;
						ErrMsg += "\n\t'" + FullMethodDesc (mb) + "': '" + argName + "' is not a parameter";
					}
				}
			}
			if (error)
				return null;
			return orderedArgs;
		}
		
/*
		static bool compare_name_filter (MemberInfo m, object filterCriteria)
		{
			return (m.Name == ((string) filterCriteria));
		}
*/

		public static MethodBase OverloadResolve (EmitContext ec, MethodGroupExpr me,
							  ref ArrayList Arguments, Location loc)
		{
			bool isLateBindingRequired;
			return OverloadResolve (ec, me, ref Arguments, loc, out isLateBindingRequired);	
		}

		// We need an overload for OverloadResolve because Invocation.DoResolve
		// must pass Arguments by reference, since a later call to IsApplicable
		// can change the argument list if optional parameters are defined
		// in the method declaration
		public static MethodBase OverloadResolve (EmitContext ec, MethodGroupExpr me,
							  ArrayList Arguments, Location loc)
		{
			ArrayList a = Arguments;
			return OverloadResolve (ec, me, ref a, loc);	
		}

/*
		static string ToString(MethodBase mbase)
		{
			if (mbase == null)
				return "NULL";

			if (mbase is MethodBuilder)
			{
				MethodBuilder mb = (MethodBuilder) mbase;
				String res = mb.ReturnType + " (";
				ParameterInfo [] parms = mb.GetParameters();
				for (int i = 0; i < parms.Length; i++) {
					if (i != 0)
						res += " ";
					res += parms[i].ParameterType;
				}
				res += ")";
				return res;
			}

			return mbase.ToString();
		}
*/
		
		/// <summary>
		///   Find the Applicable Function Members (7.4.2.1)
		///
		///   me: Method Group expression with the members to select.
		///       it might contain constructors or methods (or anything
		///       that maps to a method).
		///
		///   Arguments: ArrayList containing resolved Argument objects.
		///
		///   loc: The location if we want an error to be reported, or a Null
		///        location for "probing" purposes.
		///
		///   isLateBindingRequired : Flag to indicate that this method call is
		///                           is a candidate for late binding. Set to true if
		///                           there is atleast one object argument and we get
		///                           * Two or more candidates that require widening conv
		///                           * Two or more candidates require narrowing conversions
		///                             (for object arguments **only**)
		///   Returns: The MethodBase (either a ConstructorInfo or a MethodInfo)
		///            that is the best match of me on Arguments.
		///
		/// </summary>
		public static MethodBase OverloadResolve (EmitContext ec, MethodGroupExpr me,
							  ref ArrayList Arguments, Location loc,
							  out bool isLateBindingRequired)
		{
			MethodBase method = null;
			int argument_count;
			ArrayList candidates = new ArrayList ();
			ArrayList lateBindingCandidates = new ArrayList ();
			Hashtable expanded_candidates = new Hashtable();
			int narrow_count = 0;
			bool narrowing_candidate = false;
			errorMsg = "";
			isLateBindingRequired = false;
			CaseInsensitiveHashtable namedArgs = new CaseInsensitiveHashtable ();

			if (Arguments == null)
				argument_count = 0;
			else
				argument_count = Arguments.Count;

			if (!CheckNamedArguments (Arguments, loc))
				return null;

			if (!GetNamedArgPos (Arguments, ref namedArgs, loc))
				return null;

			ArrayList newarglist = Arguments;
			foreach (MethodBase candidate in me.Methods){
				bool candidate_expanded, object_args_present;
				newarglist = Arguments;
				if (argument_count > 0 && namedArgs.Count != 0) {
					newarglist = ReorderArguments (candidate, Arguments, namedArgs, ref errorMsg, loc);
					if (newarglist == null)
						continue;
				}

				ConversionType m = IsApplicable (ec, newarglist, candidate, out candidate_expanded, out object_args_present);
				if (candidate_expanded)
					expanded_candidates [candidate] = candidate;
				if (m == ConversionType.None)
					continue;
				else if (m == ConversionType.Narrowing) {
					if (object_args_present)   // if the narrowing conversion was due 
								   // to the argument being an object
						lateBindingCandidates.Add (candidate);
					if (method == null) {
						method = candidate;
						narrowing_candidate = true;
					} 
					narrow_count++;
				} else if (m == ConversionType.Widening) {
					if (method == null || narrowing_candidate) {
						method = candidate;
						narrowing_candidate = false;
					} else {
						Applicability res = BetterFunction (ec, Arguments, candidate, method, true, loc);
						if (res == Applicability.Same)
							continue; // should check it overrides?
						if (res == Applicability.Better)
							method = candidate;
					}
					candidates.Add (candidate);
				}
			}

			if (candidates.Count == 0) {
				if (lateBindingCandidates.Count > 1) {
					isLateBindingRequired = true;
					return null;
				}

				if (narrow_count > 1) {
					if (lateBindingCandidates.Count == 1)
						method = (MethodBase) lateBindingCandidates [0];
					else 
						method = null;
				} else if (narrow_count == 1)
					candidates = null;
			} else if (candidates.Count == 1) {
				method = (MethodBase)candidates [0];
				candidates = null;
			} else
				narrow_count  = 0;

			if (method == null) {
				//
				// Okay so we have failed to find anything so we
				// return by providing info about the closest match
				//
				for (int i = 0; i < me.Methods.Length; ++i) {

					MethodBase c = (MethodBase) me.Methods [i];
					ParameterData pd = GetParameterData (c);

					if (pd.Count != argument_count)
						continue;

					bool dummy;
					if (narrow_count != 0) {
					 	if (IsApplicable (ec, Arguments, c, out dummy) == ConversionType.None)
							continue;
						Report.Error (1502, loc,
							"Overloaded match for method '" +
							FullMethodDesc (c) +
							"' requires narrowing conversionss");
					}

					VerifyArgumentsCompat (ec, Arguments, argument_count, c, false,
							       null, loc);
				}
				
				return null;
			}

			//
			// Now check that there are no ambiguities i.e the selected method
			// should be better than all the others
			//

			if (candidates != null) {
				foreach (MethodBase candidate in candidates){
 					if (candidate == method)
 						continue;


					if (BetterFunction (ec, Arguments, candidate, method,
								false, loc) == Applicability.Better) {
 						Report.Error (
 							121, loc,
 							"Ambiguous call of '" + me.Name + "' when selecting function due to implicit casts");
						return null;
 					}
				}
			}

			//
			// And now check if the arguments are all compatible, perform conversions
			// if necessary etc. and return if everything is all right
			//
			if (method == null)
				return null;

			bool chose_params_expanded = expanded_candidates.Contains (method);

			newarglist = Arguments;
			if (argument_count > 0 && namedArgs.Count != 0) {
				string err = "";
				newarglist = ReorderArguments (method, Arguments, namedArgs, ref err, loc);
				if (newarglist == null)
					return null;
			}

			Arguments = ConstructArgumentList(ec, newarglist, namedArgs, method);
			if (VerifyArgumentsCompat (ec, Arguments, argument_count, method,
						   chose_params_expanded, null, loc))
			{
				return method;
			}
			else
				return null;
		}

		internal static bool CheckNamedArguments (ArrayList Arguments, Location loc) 
		{
			if (Arguments == null || Arguments.Count == 0)
				return true;
			
			bool namedArgFound = false;
			for (int index = 0; index < Arguments.Count; index ++) {
				Argument a = (Argument) Arguments [index];
				if (a.ParamName == null || a.ParamName == "") {
					if (namedArgFound) {
						Report.Error (30241, loc,
							"Named argument expected");
						return false;
					}
				} else
					namedArgFound = true;
			}

			return true;
		}

		internal static bool GetNamedArgPos (ArrayList Arguments, ref CaseInsensitiveHashtable namedArgs, Location loc) 
		{
			namedArgs.Clear ();
			if (Arguments == null || Arguments.Count == 0)
				return true;
			for (int index = 0; index < Arguments.Count; index ++) {
				Argument a = (Argument) Arguments [index];
				if (a.ParamName == null || a.ParamName == "")
					// none of the args are named
					return true;
				if (namedArgs.Contains (a.ParamName)) {
					Report.Error (30274, loc, "Parameter '" + a.ParamName +"'already has a matching argument");
					return false;
				}
				namedArgs.Add (a.ParamName, index);
			}
			return true;
		}

		public static ArrayList ConstructArgumentList (EmitContext ec, ArrayList Arguments, CaseInsensitiveHashtable namedArgs, MethodBase method)
		{
			ArrayList newarglist = new ArrayList();
			int arg_count = Arguments == null ? 0 : Arguments.Count;

			ParameterData pd = GetParameterData (method);
			bool argNamesGiven = (namedArgs.Count > 0);
			for (int i = 0; i < arg_count; i++) {
				Argument a = (Argument) Arguments [i];
				Type param_type = pd.ParameterType (i);

				bool IsDelegate = TypeManager.IsDelegateType (param_type);
				if (a.ArgType == Argument.AType.NoArg) {
					if (argNamesGiven)
						a = new Argument (pd.ParameterName (i), pd.DefaultValue (i), Argument.AType.Expression);
					else
						a = new Argument (pd.DefaultValue (i), Argument.AType.Expression);
					a.Resolve (ec, Location.Null);
				}

				if (IsDelegate)	{	
					if (a.ArgType == Argument.AType.AddressOf) {
						a = new Argument ((Expression) a.Expr, Argument.AType.Expression);
						ArrayList args = new ArrayList();
						args.Add (a);
						string param_name = pd.ParameterDesc(i).Replace('+', '.');
						Expression pname = MonoBASIC.Parser.DecomposeQI (param_name, Location.Null);

						New temp_new = new New ((Expression)pname, args, Location.Null);
						Expression del_temp = temp_new.DoResolve(ec);
						a = new Argument (del_temp, Argument.AType.Expression);
						a.Resolve(ec, Location.Null);
					}
				}
				if ((pd.ParameterModifier (i) & Parameter.Modifier.REF) != 0) {
					a.ArgType = Argument.AType.Ref;
					a.Resolve(ec, Location.Null);
				}	

				newarglist.Add (a);
			}

			if (HasArrayParameter (pd) && arg_count == pd.Count - 1)
				return newarglist;

			for (int i = arg_count; i < pd.Count; i++) {
				Expression e = pd.DefaultValue (i);
				Argument a = null;
				if (argNamesGiven)
					a = new Argument (e, Argument.AType.Expression);
				else
					a = new Argument (pd.ParameterName (i), e, Argument.AType.Expression);
				if ((pd.ParameterModifier (i) & Parameter.Modifier.REF) != 0)
					a.ArgType = Argument.AType.Ref;
				e.Resolve (ec);
				a.Resolve (ec, Location.Null);
				newarglist.Add (a);
			}

			return newarglist;
		}

		public static bool VerifyArgumentsCompat (EmitContext ec, ArrayList Arguments,
			int argument_count,
			MethodBase method, 
			bool chose_params_expanded,
			Type delegate_type,
			Location loc)
		{
			return (VerifyArgumentsCompat (ec, Arguments, argument_count,
				method, chose_params_expanded, delegate_type, loc, null));
		}
										  
		public static bool VerifyArgumentsCompat (EmitContext ec, 
							  ArrayList Arguments,
							  int argument_count,
							  MethodBase method, 
							  bool chose_params_expanded,
							  Type delegate_type,
							  Location loc,
							  string InvokingProperty)
		{
			ParameterData pd = GetParameterData (method);
			int pd_count = pd.Count;

			for (int j = 0; j < argument_count; j++) {
				Argument a = (Argument) Arguments [j];
				Expression a_expr = a.Expr;
				Type parameter_type = pd.ParameterType(j);
					
				if (parameter_type == null)
				{
					Error_WrongNumArguments(loc, (InvokingProperty == null)?((delegate_type == null)?FullMethodDesc (method):delegate_type.ToString ()):InvokingProperty, argument_count);
					return false;	
				}
				if (pd.ParameterModifier (j) == Parameter.Modifier.PARAMS &&
			    	chose_params_expanded)
					parameter_type = TypeManager.TypeToCoreType (parameter_type.GetElementType ());
				// By pass conversion for foll. case and handle it in EmitArguments()

				if (a.ArgType != Argument.AType.Ref && a.Type != parameter_type){
					Expression conv;
					
					conv = ConvertImplicit (ec, a_expr, parameter_type, loc);

					if (conv == null) {
						if (!Location.IsNull (loc)) {
							if (delegate_type == null) 
								if (InvokingProperty == null)
									Report.Error (1502, loc,
										"The best overloaded match for method '" +
										FullMethodDesc (method) +
										"' has some invalid arguments");
								else
									Report.Error (1502, loc,
										"Property '" +
										InvokingProperty +
										"' has some invalid arguments");
							else
								Report.Error (1594, loc,
									      "Delegate '" + delegate_type.ToString () +
									      "' has some invalid arguments.");
							Report.Error (1503, loc,
							 "Argument " + (j+1) +
							 ": Cannot convert from '" + Argument.FullDesc (a) 
							 + "' to '" + pd.ParameterDesc (j) + "'");
						}
						
						return false;
					}
					
					//
					// Update the argument with the implicit conversion
					//
					if (a_expr != conv)
						a.Expr = conv;
				}

				Parameter.Modifier a_mod = a.GetParameterModifier () &
					~(Parameter.Modifier.REF);
				Parameter.Modifier p_mod = pd.ParameterModifier (j) &
					~(Parameter.Modifier.REF | Parameter.Modifier.OPTIONAL);

				if (a_mod != p_mod &&
				    pd.ParameterModifier (pd_count - 1) != Parameter.Modifier.PARAMS) {
					if (!Location.IsNull (loc)) {
						Report.Error (1502, loc,
						       "The best overloaded match for method '" + FullMethodDesc (method)+
						       "' has some invalid arguments");
						Report.Error (1503, loc,
						       "Argument " + (j+1) +
						       ": Cannot convert from '" + Argument.FullDesc (a) 
						       + "' to '" + pd.ParameterDesc (j) + "'");
					}
					
					return false;
				}
			}

			return true;
		}
	
		public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
		{
			this.is_left_hand = true;
			Expression expr_to_return = DoResolve (ec);

			if (expr_to_return is IndexerAccess) {
				IndexerAccess ia = expr_to_return as IndexerAccess;
				expr_to_return = ia.DoResolveLValue (ec, right_side);
			}
			return expr_to_return;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			//
			// First, resolve the expression that is used to
			// trigger the invocation
			//
			Expression expr_to_return = null;
			Expression temp = null;

			if (expr is BaseAccess)
				is_base = true;

			ResolveFlags flags;
			if ((ec.ReturnType != null) && (expr.ToString() == ec.BlockName)) {
				ec.InvokingOwnOverload = true;
				flags = ResolveFlags.MethodGroup;
				temp = expr.Resolve (ec, flags);
				ec.InvokingOwnOverload = false;
			}
			else				
			{
				ec.InvokingOwnOverload = false;
				flags = ResolveFlags.VariableOrValue | ResolveFlags.MethodGroup;
				temp = expr.Resolve (ec, flags);
			}

			if (temp == null) {
				if (is_left_hand)
					return null;
			
				if (expr is MemberAccess) {
					MemberAccess m = expr as MemberAccess;
					if (m.Expr.Type == TypeManager.object_type) {
						StatementSequence etmp = new StatementSequence (ec.CurrentBlock, 
										loc, expr, Arguments, 
										is_retval_required, is_left_hand);
						if (!etmp.ResolveArguments (ec))
							return null;
						etmp.GenerateLateBindingStatements();
						this.is_latebinding = true;
						return etmp.Resolve (ec);
					}
				}
				return null;
			}
	
			expr = temp;

			if (expr is Invocation) {
				// FIXME Calls which return an Array are not resolved (here or in the grammar)
				expr = expr.Resolve(ec);
			}

			if (!(expr is MethodGroupExpr)) 
			{
				Type expr_type = expr.Type;

				if (expr_type != null)
				{
					bool IsDelegate = TypeManager.IsDelegateType (expr_type);
					if (IsDelegate)
						return (new DelegateInvocation (
							this.expr, Arguments, loc)).Resolve (ec);
				}
			}

			//
			// Next, evaluate all the expressions in the argument list
			//
			if (Arguments != null)
			{
				foreach (Argument a in Arguments)
				{
					if ((a.ArgType == Argument.AType.NoArg) && (!(expr is MethodGroupExpr)))
						Report.Error (999, "This item cannot have empty arguments");

					if (!a.Resolve (ec, loc))
						return null;				
				}
			}
			
			if (expr is MethodGroupExpr) 
			{
				MethodGroupExpr mg = (MethodGroupExpr) expr;
				bool isLateBindingRequired = false;
				method = OverloadResolve (ec, mg, ref Arguments, loc, out isLateBindingRequired);
				if (method == null)
				{
					if (isLateBindingRequired) {
						Expression type_expr = new TypeOf (Parser.DecomposeQI (mg.DeclaringType.Name, loc), loc);
						StatementSequence etmp = new StatementSequence (ec.CurrentBlock, 
									loc, null, mg.Name, type_expr, 
									Arguments, is_retval_required, is_left_hand);
						if (! etmp.ResolveArguments (ec))
							return null;
						etmp.GenerateLateBindingStatements ();
						return etmp.Resolve (ec);
					}
					Error (30455,
						"Could not find any applicable function to invoke for this argument list" + errorMsg);
					return null;
				}

				if ((method as MethodInfo) != null) 
				{
					MethodInfo mi = method as MethodInfo;
					type = TypeManager.TypeToCoreType (mi.ReturnType);
					if (!mi.IsStatic && !mg.IsExplicitImpl && (mg.InstanceExpression == null))
						SimpleName.Error_ObjectRefRequired (ec, loc, mi.Name);
				}

				if ((method as ConstructorInfo) != null) 
				{
					ConstructorInfo ci = method as ConstructorInfo;
					type = TypeManager.void_type;
					if (!ci.IsStatic && !mg.IsExplicitImpl && (mg.InstanceExpression == null))
						SimpleName.Error_ObjectRefRequired (ec, loc, ci.Name);
				}

				if (type.IsPointer)
				{
					if (!ec.InUnsafe)
					{
						UnsafeError (loc);
						return null;
					}
				}
				eclass = ExprClass.Value;
				expr_to_return = this;
				return expr_to_return;
			}

			if (expr is PropertyExpr) 
			{
				PropertyExpr pe = ((PropertyExpr) expr);
				if (pe.PropertyArgs != null)
					goto skip_already_resolved_property;
				pe.PropertyArgs = (ArrayList) Arguments;
				MethodBase mi = pe.PropertyInfo.GetGetMethod(true);
				int argCount = 0;
				if (Arguments != null)
					argCount = Arguments.Count;

				bool expanded = false;
				if (IsApplicable(ec, pe.PropertyArgs, mi, out expanded) != ConversionType.None) {
					if(VerifyArgumentsCompat (ec, pe.PropertyArgs,
						argCount, mi, expanded, null, loc, pe.Name))
					{
						expr_to_return = pe.DoResolve (ec);
						expr_to_return.eclass = ExprClass.PropertyAccess;
						Arguments = new ArrayList ();
						return expr_to_return;
					}
					else
					{
						throw new Exception("Error resolving Property Access expression\n" + pe.ToString());
					}
				} else {
					pe.PropertyArgs = new ArrayList ();
					if (VerifyArgumentsCompat (ec, pe.PropertyArgs,
						0, mi, false, null, loc, pe.Name)) {
						expr = pe.DoResolve (ec);
						expr.eclass = ExprClass.PropertyAccess;
					} else {
						throw new Exception("Error resolving Property Access expression\n" + pe.ToString());
					}
				}
			}

			skip_already_resolved_property:
			if (expr.Type.IsArray) {
				// If we are here, expr must be an ArrayAccess
				ArrayList idxs = new ArrayList();
				foreach (Argument a in Arguments)
				{
					idxs.Add (a.Expr);
				}
				ElementAccess ea = new ElementAccess (expr, idxs, expr.Location);
				ArrayAccess aa = new ArrayAccess (ea, expr.Location);
				expr_to_return = aa.DoResolve(ec);
				expr_to_return.eclass = ExprClass.Variable;
			} else {
				//
				// check whether this is a indexer
				//
				ArrayList idxs = new ArrayList();
				foreach (Argument a in Arguments) {
					idxs.Add (a.Expr);
				}
				ElementAccess ea = new ElementAccess (expr, idxs, expr.Location);
				IndexerAccess ia = new IndexerAccess (ea, expr.Location);
				if (!is_left_hand)
					expr_to_return = ia.DoResolve(ec);
				else
					expr_to_return = ia.DoResolve(ec);
				//
				// Since all the above are failed we need to do
				// late binding
				//
				if (expr_to_return == null) {

					// We can't resolve now, but we
					// have to try to access the array with a call
					// to LateIndexGet/Set in the runtime
					if (! is_left_hand) {
						StatementSequence etmp = new StatementSequence (ec.CurrentBlock, 
									loc, ia, Arguments, 
									true, false);
						if (!etmp.ResolveArguments (ec))
							return null;
						etmp.GenerateLateBindingStatements();
						return etmp.Resolve (ec);
					}
					return null;
				}
			}

			return expr_to_return;
		}

        	static void Error_WrongNumArguments (Location loc, String name, int arg_count)
        	{
            		Report.Error (1501, loc, "No overload for method `" + name + "' takes `" +
                                      arg_count + "' arguments");
        	}

		// <summary>
		//   Emits the list of arguments as an array
		// </summary>
		static void EmitParams (EmitContext ec, int idx, ArrayList arguments)
		{
			ILGenerator ig = ec.ig;
			int count = arguments.Count - idx;
			Argument a = (Argument) arguments [idx];
			Type t = a.Expr.Type;
			string array_type = t.FullName + "[]";
			LocalBuilder array;

			array = ig.DeclareLocal (TypeManager.LookupType (array_type));
			IntConstant.EmitInt (ig, count);
			ig.Emit (OpCodes.Newarr, TypeManager.TypeToCoreType (t));
			ig.Emit (OpCodes.Stloc, array);

			int top = arguments.Count;
			for (int j = idx; j < top; j++){
				a = (Argument) arguments [j];
				
				ig.Emit (OpCodes.Ldloc, array);
				IntConstant.EmitInt (ig, j - idx);
				a.Emit (ec);
				
				ArrayAccess.EmitStoreOpcode (ig, t);
			}
			ig.Emit (OpCodes.Ldloc, array);
		}
		
		/// <summary>
		///   Emits a list of resolved Arguments that are in the arguments
		///   ArrayList.
		/// </summary>
		public static void EmitArguments (EmitContext ec, MethodBase mb, ArrayList arguments)
		{
			ParameterData pd = GetParameterData (mb);

			//
			// If we are calling a params method with no arguments, special case it
			//
			if (arguments == null){
				if (pd.Count > 0 &&
				    pd.ParameterModifier (0) == Parameter.Modifier.PARAMS){
					ILGenerator ig = ec.ig;

					IntConstant.EmitInt (ig, 0);
					ig.Emit (OpCodes.Newarr, pd.ParameterType (0).GetElementType ());
				}
				return;
			}

			int top = arguments.Count;

			for (int i = 0; i < top; i++){
				Argument a = (Argument) arguments [i];
				Type parameter_type = pd.ParameterType(i);
				Type argtype = a.Type;
				Type arg_expr_type = a.Expr.Type;

				if (pd.ParameterModifier (i) == Parameter.Modifier.PARAMS){
					//
					// Special case if we are passing the same data as the
					// params argument, do not put it in an array.
					//
					if (pd.ParameterType (i) == a.Type)
						a.Emit (ec);
					else
						EmitParams (ec, i, arguments);
					return;
				}
				if ((a.ArgType == Argument.AType.Ref ) &&
					(parameter_type != arg_expr_type ||
					 ! (a.Expr is IMemoryLocation))) {
					
					 LocalTemporary localtmp = new LocalTemporary (ec, parameter_type ); 

					if((arg_expr_type != parameter_type) && (a.ArgType == Argument.AType.Ref)) {					 
						Expression e = ConvertImplicit (ec, a.Expr, parameter_type, Location.Null);
						is_byref_conversion = true;
                                        	e.Emit (ec);
					} else 
						a.Expr.Emit (ec);
					


					if (tempvars == null)
						tempvars = new ArrayList ();
					if (a.Expr is IMemoryLocation && is_byref_conversion ) {
						Expression conv;
						if(argtype.IsByRef)
							argtype = argtype.GetElementType();
						conv = ConvertImplicit (ec, localtmp, argtype, Location.Null);
						 tempvars.Add (new Assign (a.Expr, conv, Location.Null));

					}
                                       	localtmp.Store (ec);
                                    	a = new Argument (localtmp, a.ArgType);
				}
                                a.Emit (ec);
                        }



			if (pd.Count > top &&
			    pd.ParameterModifier (top) == Parameter.Modifier.PARAMS){
				ILGenerator ig = ec.ig;

				IntConstant.EmitInt (ig, 0);
				ig.Emit (OpCodes.Newarr, pd.ParameterType (top).GetElementType ());
			}
		}

		/// <remarks>
		///   is_base tells whether we want to force the use of the 'call'
		///   opcode instead of using callvirt.  Call is required to call
		///   a specific method, while callvirt will always use the most
		///   recent method in the vtable.
		///
		///   is_static tells whether this is an invocation on a static method
		///
		///   instance_expr is an expression that represents the instance
		///   it must be non-null if is_static is false.
		///
		///   method is the method to invoke.
		///
		///   Arguments is the list of arguments to pass to the method or constructor.
		/// </remarks>
		public static void EmitCall (EmitContext ec, bool is_base,
					     bool is_static, Expression instance_expr,
					     MethodBase method, ArrayList Arguments, Location loc)
		{
			EmitCall (ec, is_base, is_static, instance_expr, method, Arguments, null, loc);
		}
		
		public static void EmitCall (EmitContext ec, bool is_base,
			bool is_static, Expression instance_expr,
			MethodBase method, ArrayList Arguments, ArrayList prop_args, Location loc)
		{
			ILGenerator ig = ec.ig;
			bool struct_call = false;
			bool is_myclass = false;

			if (instance_expr is This && ((This) instance_expr).AccessType == This.TypeOfAccess.MyClass) 
				is_myclass = true;

			Type decl_type = method.DeclaringType;

			if (!RootContext.StdLib) 
			{
				// Replace any calls to the system's System.Array type with calls to
				// the newly created one.
				if (method == TypeManager.system_int_array_get_length)
					method = TypeManager.int_array_get_length;
				else if (method == TypeManager.system_int_array_get_rank)
					method = TypeManager.int_array_get_rank;
				else if (method == TypeManager.system_object_array_clone)
					method = TypeManager.object_array_clone;
				else if (method == TypeManager.system_int_array_get_length_int)
					method = TypeManager.int_array_get_length_int;
				else if (method == TypeManager.system_int_array_get_lower_bound_int)
					method = TypeManager.int_array_get_lower_bound_int;
				else if (method == TypeManager.system_int_array_get_upper_bound_int)
					method = TypeManager.int_array_get_upper_bound_int;
				else if (method == TypeManager.system_void_array_copyto_array_int)
					method = TypeManager.void_array_copyto_array_int;
			}

			//
			// This checks the 'ConditionalAttribute' on the method, and the
			// ObsoleteAttribute
			//
			TypeManager.MethodFlags flags = TypeManager.GetMethodFlags (method, loc);
			if ((flags & TypeManager.MethodFlags.IsObsoleteError) != 0)
				return;
			if ((flags & TypeManager.MethodFlags.ShouldIgnore) != 0)
				return;
			
			if (!is_static)
			{
				if (decl_type.IsValueType)
					struct_call = true;
				//
				// If this is ourselves, push "this"
				//
				if (instance_expr == null)
				{
					ig.Emit (OpCodes.Ldarg_0);
				} 
				else 
				{
					//
					// Push the instance expression
					//
					if (instance_expr.Type.IsValueType)
					{
						//
						// Special case: calls to a function declared in a 
						// reference-type with a value-type argument need
						// to have their value boxed.  

						struct_call = true;
						if (decl_type.IsValueType)
						{
							//
							// If the expression implements IMemoryLocation, then
							// we can optimize and use AddressOf on the
							// return.
							//
							// If not we have to use some temporary storage for
							// it.
							if (instance_expr is IMemoryLocation)
							{
								((IMemoryLocation)instance_expr).
									AddressOf (ec, AddressOp.LoadStore);
							}
							else 
							{
								Type t = instance_expr.Type;
								
								instance_expr.Emit (ec);
								LocalBuilder temp = ig.DeclareLocal (t);
								ig.Emit (OpCodes.Stloc, temp);
								ig.Emit (OpCodes.Ldloca, temp);
							}
						} 
						else 
						{
							instance_expr.Emit (ec);
							ig.Emit (OpCodes.Box, instance_expr.Type);
						} 
					} 
					else
						instance_expr.Emit (ec);
				}
			}
			
			if (prop_args != null && prop_args.Count > 0)
			{
				if (Arguments == null) 
					Arguments = new ArrayList();

				for (int i = prop_args.Count-1; i >=0 ; i--) 
				{
					Arguments.Insert (0,prop_args[i]);
				}

			}

			EmitArguments (ec, method, Arguments);

			if (is_static || struct_call || is_base || is_myclass)
			{
				if (method is MethodInfo) 
				{
					ig.Emit (OpCodes.Call, (MethodInfo) method);
				} 
				else
					ig.Emit (OpCodes.Call, (ConstructorInfo) method);
			} 
			else 
			{
				if (method is MethodInfo)
					ig.Emit (OpCodes.Callvirt, (MethodInfo) method);
				else
					ig.Emit (OpCodes.Callvirt, (ConstructorInfo) method);
			}
		}
		
/*
		static void EmitPropertyArgs (EmitContext ec, ArrayList prop_args)
		{
			int top = prop_args.Count;

			for (int i = 0; i < top; i++)
			{
				Argument a = (Argument) prop_args [i];
				a.Emit (ec);
			}
		}
*/

		public override void Emit (EmitContext ec)
		{
			MethodGroupExpr mg = (MethodGroupExpr) this.expr;

			EmitCall (
				ec, is_base, method.IsStatic, mg.InstanceExpression, method, Arguments, loc);
		}
		
		public override void EmitStatement (EmitContext ec)
		{
			Emit (ec);

			// 
			// Pop the return value if there is one
			//
			if (method is MethodInfo){
				Type ret = ((MethodInfo)method).ReturnType;
				if ((TypeManager.TypeToCoreType (ret) != TypeManager.void_type) && !this.is_latebinding) {
					ec.ig.Emit (OpCodes.Pop);

					if (tempvars != null) {
						foreach (ExpressionStatement s in tempvars)
							s.EmitStatement (ec);
						tempvars.Clear ();
					}
				}
				
			}
		}
	}

	//
	// This class is used to "disable" the code generation for the
	// temporary variable when initializing value types.
	//
	class EmptyAddressOf : EmptyExpression, IMemoryLocation {
		public void AddressOf (EmitContext ec, AddressOp Mode)
		{
			// nothing
		}
	}
	
	/// <summary>
	///    Implements the new expression 
	/// </summary>
	public class New : ExpressionStatement {
		public readonly ArrayList Arguments;
		public readonly Expression RequestedType;

		MethodBase method = null;

		//
		// If set, the new expression is for a value_target, and
		// we will not leave anything on the stack.
		//
		Expression value_target;
		bool value_target_set = false;
		public bool isDelegate = false;
		
		public New (Expression requested_type, ArrayList arguments, Location l)
		{
			RequestedType = requested_type;
			Arguments = arguments;
			loc = l;
		}

		public Expression ValueTypeVariable {
			get {
				return value_target;
			}

			set {
				value_target = value;
				value_target_set = true;
			}
		}

		//
		// This function is used to disable the following code sequence for
		// value type initialization:
		//
		// AddressOf (temporary)
		// Construct/Init
		// LoadTemporary
		//
		// Instead the provide will have provided us with the address on the
		// stack to store the results.
		//
		static Expression MyEmptyExpression;
		
		public void DisableTemporaryValueType ()
		{
			if (MyEmptyExpression == null)
				MyEmptyExpression = new EmptyAddressOf ();

			//
			// To enable this, look into:
			// test-34 and test-89 and self bootstrapping.
			//
			// For instance, we can avoid a copy by using 'newobj'
			// instead of Call + Push-temp on value types.
//			value_target = MyEmptyExpression;
		}
		
		public override Expression DoResolve (EmitContext ec)
		{
			if (this.isDelegate) {
				// if its a delegate resolve the type of RequestedType first
				Expression dtype = RequestedType.Resolve(ec);
				string ts = (dtype.Type.ToString()).Replace ('+','.');
				dtype = Mono.MonoBASIC.Parser.DecomposeQI (ts, Location.Null);

				type = ec.DeclSpace.ResolveType (dtype, false, loc);
			}
			else
				type = ec.DeclSpace.ResolveType (RequestedType, false, loc);
			
			if (type == null)
				return null;
			
			bool IsDelegate = TypeManager.IsDelegateType (type);
			
			if (IsDelegate)
				return (new NewDelegate (type, Arguments, loc)).Resolve (ec);

			if (type.IsInterface || type.IsAbstract){
				Error (
					30376, "It is not possible to create instances of Interfaces " +
					"or classes marked as MustInherit");
				return null;
			}

			bool is_struct = false;
			is_struct = type.IsValueType;
			eclass = ExprClass.Value;

			//
			// SRE returns a match for .ctor () on structs (the object constructor), 
			// so we have to manually ignore it.
			//
			if (is_struct && Arguments == null)
				return this;
			
			Expression ml;
			ml = MemberLookupFinal (ec, type, ".ctor",
						MemberTypes.Constructor,
						AllBindingFlags | BindingFlags.Public, loc);

			if (ml == null)
				return null;
			
			if (! (ml is MethodGroupExpr)){
				if (!is_struct){
					ml.Error118 ("method group");
					return null;
				}
			}

			if (ml != null) {
				if (Arguments != null){
					foreach (Argument a in Arguments){
						if (!a.Resolve (ec, loc))
							return null;
					}
				}

				method = Invocation.OverloadResolve (ec, (MethodGroupExpr) ml,
								     Arguments, loc);
				
			}

			if (method == null) { 
                                if (!is_struct || Arguments.Count > 0) {
        				Error (1501,
	        			       "New invocation: Can not find a constructor for " +
		        		       "this argument list");
			        	return null;
                                }
			}
			return this;
		}

		//
		// This DoEmit can be invoked in two contexts:
		//    * As a mechanism that will leave a value on the stack (new object)
		//    * As one that wont (init struct)
		//
		// You can control whether a value is required on the stack by passing
		// need_value_on_stack.  The code *might* leave a value on the stack
		// so it must be popped manually
		//
		// If we are dealing with a ValueType, we have a few
		// situations to deal with:
		//
		//    * The target is a ValueType, and we have been provided
		//      the instance (this is easy, we are being assigned).
		//
		//    * The target of New is being passed as an argument,
		//      to a boxing operation or a function that takes a
		//      ValueType.
		//
		//      In this case, we need to create a temporary variable
		//      that is the argument of New.
		//
		// Returns whether a value is left on the stack
		//
		bool DoEmit (EmitContext ec, bool need_value_on_stack)
		{
			bool is_value_type = type.IsValueType;
			ILGenerator ig = ec.ig;

			if (is_value_type){
				IMemoryLocation ml;

				// Allow DoEmit() to be called multiple times.
				// We need to create a new LocalTemporary each time since
				// you can't share LocalBuilders among ILGeneators.
				if (!value_target_set)
					value_target = new LocalTemporary (ec, type);
					
				ml = (IMemoryLocation) value_target;
				ml.AddressOf (ec, AddressOp.Store);
			}

			if (method != null)
				Invocation.EmitArguments (ec, method, Arguments);

			if (is_value_type){
				if (method == null)
					ig.Emit (OpCodes.Initobj, type);
				else 
					ig.Emit (OpCodes.Call, (ConstructorInfo) method);
                                if (need_value_on_stack){
                                        value_target.Emit (ec);
                                        return true;
                                }
                                return false;
			} else {
				ig.Emit (OpCodes.Newobj, (ConstructorInfo) method);
				return true;
			}
		}

		public override void Emit (EmitContext ec)
		{
			DoEmit (ec, true);
		}
		
		public override void EmitStatement (EmitContext ec)
		{
			if (DoEmit (ec, false))
				ec.ig.Emit (OpCodes.Pop);
		}
	}

	/// <summary>
	///   14.5.10.2: Represents an array creation expression.
	/// </summary>
	///
	/// <remarks>
	///   There are two possible scenarios here: one is an array creation
	///   expression that specifies the dimensions and optionally the
	///   initialization data and the other which does not need dimensions
	///   specified but where initialization data is mandatory.
	/// </remarks>
	public class ArrayCreation : ExpressionStatement {
		Expression requested_base_type;
		ArrayList initializers;

		//
		// The list of Argument types.
		// This is used to construct the 'newarray' or constructor signature
		//
		ArrayList arguments;

		//
		// Method used to create the array object.
		//
		MethodBase new_method = null;
		
		Type array_element_type;
		Type underlying_type;
		bool is_one_dimensional = false;
		bool is_builtin_type = false;
		bool expect_initializers = false;
		int num_arguments = 0;
		int dimensions = 0;
		string rank;

		ArrayList array_data;

		Hashtable bounds;

		//
		// The number of array initializers that we can handle
		// via the InitializeArray method - through EmitStaticInitializers
		//
		int num_automatic_initializers;
		
		public ArrayCreation (Expression requested_base_type, ArrayList exprs, string rank, ArrayList initializers, Location l)
		{
			this.requested_base_type = requested_base_type;
			this.initializers = initializers;
			this.rank = rank;
			loc = l;

			arguments = new ArrayList ();

			foreach (Expression e in exprs) {
				arguments.Add (new Argument (e, Argument.AType.Expression));
				num_arguments++;
			}
		}

		public ArrayCreation (Expression requested_base_type, string rank, ArrayList initializers, Location l)
		{
			this.requested_base_type = requested_base_type;
			this.initializers = initializers;
			this.rank = rank;
			loc = l;

			//this.rank = rank.Substring (0, rank.LastIndexOf ("["));
			//
			//string tmp = rank.Substring (rank.LastIndexOf ("["));
			//
			//dimensions = tmp.Length - 1;
			expect_initializers = true;
		}

		public Expression FormArrayType (Expression base_type, int idx_count, string rank)
		{
			StringBuilder sb = new StringBuilder (rank);
			
			sb.Append ("[");
			for (int i = 1; i < idx_count; i++)
				sb.Append (",");
			
			sb.Append ("]");

			return new ComposedCast (base_type, sb.ToString (), loc);
		}

		void Error_IncorrectArrayInitializer ()
		{
			Error (30567, "Incorrectly structured array initializer");
		}
		
		public bool CheckIndices (EmitContext ec, ArrayList probe, int idx, bool specified_dims)
		{
			if (specified_dims) { 
				Argument a = (Argument) arguments [idx];
				
				if (!a.Resolve (ec, loc))
					return false;
				
				if (!(a.Expr is Constant)) {
					Error (150, "A constant value is expected");
					return false;
				}
				
				int value = (int) ((Constant) a.Expr).GetValue ();
				
				if (value != probe.Count) {
					Error_IncorrectArrayInitializer ();
					return false;
				}
				
				bounds [idx] = value;
			}

			int child_bounds = -1;
			foreach (object o in probe) {
				if (o is ArrayList) {
					int current_bounds = ((ArrayList) o).Count;
					
					if (child_bounds == -1) 
						child_bounds = current_bounds;

					else if (child_bounds != current_bounds){
						Error_IncorrectArrayInitializer ();
						return false;
					}
					bool ret = CheckIndices (ec, (ArrayList) o, idx + 1, specified_dims);
					if (!ret)
						return false;
				} else {
					if (child_bounds != -1){
						Error_IncorrectArrayInitializer ();
						return false;
					}
					
					Expression tmp = (Expression) o;
					tmp = tmp.Resolve (ec);
					if (tmp == null)
						continue;

					// Console.WriteLine ("I got: " + tmp);
					// Handle initialization from vars, fields etc.

					Expression conv = ConvertImplicitRequired (
						ec, tmp, underlying_type, loc);
					
					if (conv == null) 
						return false;

					if (conv is StringConstant)
						array_data.Add (conv);
					else if (conv is Constant) {
						array_data.Add (conv);
						num_automatic_initializers++;
					} else
						array_data.Add (conv);
				}
			}

			return true;
		}
		
		public void UpdateIndices (EmitContext ec)
		{
			int i = 0;
			for (ArrayList probe = initializers; probe != null;) {
				if (probe.Count > 0 && probe [0] is ArrayList) {
					Expression e = new IntConstant (probe.Count);
					arguments.Add (new Argument (e, Argument.AType.Expression));

					bounds [i++] =  probe.Count;
					
					probe = (ArrayList) probe [0];
					
				} else {
					Expression e = new IntConstant (probe.Count);
					arguments.Add (new Argument (e, Argument.AType.Expression));

					bounds [i++] = probe.Count;
					probe = null;
				}
			}

		}
		
		public bool ValidateInitializers (EmitContext ec, Type array_type)
		{
			if (initializers == null) {
				if (expect_initializers)
					return false;
				else
					return true;
			}
			
			if (underlying_type == null)
				return false;
			
			//
			// We use this to store all the date values in the order in which we
			// will need to store them in the byte blob later
			//
			array_data = new ArrayList ();
			bounds = new Hashtable ();
			
			bool ret;

			if (arguments != null) {
				ret = CheckIndices (ec, initializers, 0, true);
				return ret;
			} else {
				arguments = new ArrayList ();

				ret = CheckIndices (ec, initializers, 0, false);
				
				if (!ret)
					return false;
				
				UpdateIndices (ec);
				
				if (arguments.Count != dimensions) {
					Error_IncorrectArrayInitializer ();
					return false;
				}

				return ret;
			}
		}

/*
		void Error_NegativeArrayIndex ()
		{
			Error (284, "Can not create array with a negative size");
		}
		
		//
		// Converts 'source' to an int, uint, long or ulong.
		//
		Expression ExpressionToArrayArgument (EmitContext ec, Expression source)
		{
			Expression target;
			
			bool old_checked = ec.CheckState;
			ec.CheckState = true;
			
			target = ConvertImplicit (ec, source, TypeManager.int32_type, loc);
			if (target == null){
				target = ConvertImplicit (ec, source, TypeManager.uint32_type, loc);
				if (target == null){
					target = ConvertImplicit (ec, source, TypeManager.int64_type, loc);
					if (target == null){
						target = ConvertImplicit (ec, source, TypeManager.uint64_type, loc);
						if (target == null)
							Expression.Error_CannotConvertImplicit (loc, source.Type, TypeManager.int32_type);
					}
				}
			} 
			ec.CheckState = old_checked;

			//
			// Only positive constants are allowed at compile time
			//
			if (target is Constant){
				if (target is IntConstant){
					if (((IntConstant) target).Value < 0){
						Error_NegativeArrayIndex ();
						return null;
					}
				}

				if (target is LongConstant){
					if (((LongConstant) target).Value < 0){
						Error_NegativeArrayIndex ();
						return null;
					}
				}
				
			}

			return target;
		}
*/

		//
		// Creates the type of the array
		//
		bool LookupType (EmitContext ec)
		{
			StringBuilder array_qualifier = new StringBuilder (rank);

			//
			// 'In the first form allocates an array instace of the type that results
			// from deleting each of the individual expression from the expression list'
			//
			if (num_arguments > 0) {
				array_qualifier.Append ("[");
				for (int i = num_arguments-1; i > 0; i--)
					array_qualifier.Append (",");
				array_qualifier.Append ("]");				
			}

			//
			// Lookup the type
			//
			Expression array_type_expr;
			array_type_expr = new ComposedCast (requested_base_type, array_qualifier.ToString (), loc);
			type = ec.DeclSpace.ResolveType (array_type_expr, false, loc);

			if (type == null)
				return false;

			underlying_type = type;
			if (underlying_type.IsArray)
				underlying_type = TypeManager.TypeToCoreType (underlying_type.GetElementType ());
			dimensions = type.GetArrayRank ();

			return true;
		}
		
		public override Expression DoResolve (EmitContext ec)
		{
			int arg_count;

			if (!LookupType (ec))
				return null;
			
			//
			// First step is to validate the initializers and fill
			// in any missing bits
			//
			if (!ValidateInitializers (ec, type))
				return null;

			if (arguments == null)
				arg_count = 0;
			else {
				arg_count = arguments.Count;
				foreach (Argument a in arguments){
					if (!a.Resolve (ec, loc))
						return null;

					Expression real_arg = ExpressionToArrayArgument (ec, a.Expr, loc);
					if (real_arg == null)
						return null;

					a.Expr = real_arg;
				}
			}
			
			array_element_type = TypeManager.TypeToCoreType (type.GetElementType ());

			if (arg_count == 1) {
				is_one_dimensional = true;
				eclass = ExprClass.Value;
				return this;
			}

			is_builtin_type = TypeManager.IsBuiltinType (type);

			if (is_builtin_type) {
				Expression ml;
				
				ml = MemberLookup (ec, type, ".ctor", MemberTypes.Constructor,
						   AllBindingFlags, loc);
				
				if (!(ml is MethodGroupExpr)) {
					ml.Error118 ("method group");
					return null;
				}
				
				if (ml == null) {
					Error (-6, "New invocation: Can not find a constructor for " +
						      "this argument list");
					return null;
				}
				
				new_method = Invocation.OverloadResolve (ec, (MethodGroupExpr) ml, arguments, loc);

				if (new_method == null) {
					Error (-6, "New invocation: Can not find a constructor for " +
						      "this argument list");
					return null;
				}
				
				eclass = ExprClass.Value;
				return this;
			} else {
				ModuleBuilder mb = CodeGen.ModuleBuilder;
				ArrayList args = new ArrayList ();
				
				if (arguments != null) {
					for (int i = 0; i < arg_count; i++)
						args.Add (TypeManager.int32_type);
				}
				
				Type [] arg_types = null;

				if (args.Count > 0)
					arg_types = new Type [args.Count];
				
				args.CopyTo (arg_types, 0);
				
				new_method = mb.GetArrayMethod (type, ".ctor", CallingConventions.HasThis, null,
							    arg_types);

				if (new_method == null) {
					Error (-6, "New invocation: Can not find a constructor for " +
						      "this argument list");
					return null;
				}
				
				eclass = ExprClass.Value;
				return this;
			}
		}

		public static byte [] MakeByteBlob (ArrayList array_data, Type underlying_type, Location loc)
		{
			int factor;
			byte [] data;
			byte [] element;
			int count = array_data.Count;

			if (underlying_type.IsEnum)
				underlying_type = TypeManager.EnumToUnderlying (underlying_type);
			
			factor = GetTypeSize (underlying_type);
			if (factor == 0)
				throw new Exception ("unrecognized type in MakeByteBlob: " + underlying_type);

			data = new byte [(count * factor + 4) & ~3];
			int idx = 0;
			
			for (int i = 0; i < count; ++i) {
				object v = array_data [i];

				if (v is EnumConstant)
					v = ((EnumConstant) v).Child;
				
				if (v is Constant && !(v is StringConstant))
					v = ((Constant) v).GetValue ();
				else {
					idx += factor;
					continue;
				}
				
				if (underlying_type == TypeManager.int64_type){
					if (!(v is Expression)){
						long val = (long) v;
						
						for (int j = 0; j < factor; ++j) {
							data [idx + j] = (byte) (val & 0xFF);
							val = (val >> 8);
						}
					}
				} else if (underlying_type == TypeManager.uint64_type){
					if (!(v is Expression)){
						ulong val = (ulong) v;

						for (int j = 0; j < factor; ++j) {
							data [idx + j] = (byte) (val & 0xFF);
							val = (val >> 8);
						}
					}
				} else if (underlying_type == TypeManager.float_type) {
					if (!(v is Expression)){
						element = BitConverter.GetBytes ((float) v);
							
						for (int j = 0; j < factor; ++j)
							data [idx + j] = element [j];
					}
				} else if (underlying_type == TypeManager.double_type) {
					if (!(v is Expression)){
						element = BitConverter.GetBytes ((double) v);

						for (int j = 0; j < factor; ++j)
							data [idx + j] = element [j];
					}
				} else if (underlying_type == TypeManager.char_type){
					if (!(v is Expression)){
						int val = (int) ((char) v);
						
						data [idx] = (byte) (val & 0xff);
						data [idx+1] = (byte) (val >> 8);
					}
				} else if (underlying_type == TypeManager.short_type){
					if (!(v is Expression)){
						int val = (int) ((short) v);
					
						data [idx] = (byte) (val & 0xff);
						data [idx+1] = (byte) (val >> 8);
					}
				} else if (underlying_type == TypeManager.ushort_type){
					if (!(v is Expression)){
						int val = (int) ((ushort) v);
					
						data [idx] = (byte) (val & 0xff);
						data [idx+1] = (byte) (val >> 8);
					}
				} else if (underlying_type == TypeManager.int32_type) {
					if (!(v is Expression)){
						int val = (int) v;
					
						data [idx]   = (byte) (val & 0xff);
						data [idx+1] = (byte) ((val >> 8) & 0xff);
						data [idx+2] = (byte) ((val >> 16) & 0xff);
						data [idx+3] = (byte) (val >> 24);
					}
				} else if (underlying_type == TypeManager.uint32_type) {
					if (!(v is Expression)){
						uint val = (uint) v;
					
						data [idx]   = (byte) (val & 0xff);
						data [idx+1] = (byte) ((val >> 8) & 0xff);
						data [idx+2] = (byte) ((val >> 16) & 0xff);
						data [idx+3] = (byte) (val >> 24);
					}
				} else if (underlying_type == TypeManager.sbyte_type) {
					if (!(v is Expression)){
						sbyte val = (sbyte) v;
						data [idx] = (byte) val;
					}
				} else if (underlying_type == TypeManager.byte_type) {
					if (!(v is Expression)){
						byte val = (byte) v;
						data [idx] = (byte) val;
					}
				} else if (underlying_type == TypeManager.bool_type) {
					if (!(v is Expression)){
						bool val = (bool) v;
						data [idx] = (byte) (val ? 1 : 0);
					}
				} else if (underlying_type == TypeManager.decimal_type){
					if (!(v is Expression)){
						int [] bits = Decimal.GetBits ((decimal) v);
						int p = idx;
						
						for (int j = 0; j < 4; j++){
							data [p++] = (byte) (bits [j] & 0xff);
							data [p++] = (byte) ((bits [j] >> 8) & 0xff);
							data [p++] = (byte) ((bits [j] >> 16) & 0xff);
							data [p++] = (byte) (bits [j] >> 24);
						}
					}
				} else
					throw new Exception ("Unrecognized type in MakeByteBlob: " + underlying_type);

                                idx += factor;
			}

			return data;
		}

		//
		// Emits the initializers for the array
		//
		void EmitStaticInitializers (EmitContext ec, bool is_expression)
		{
			//
			// First, the static data
			//
			FieldBuilder fb;
			ILGenerator ig = ec.ig;
			
			byte [] data = MakeByteBlob (array_data, underlying_type, loc);

			fb = RootContext.MakeStaticData (data);

			if (is_expression)
				ig.Emit (OpCodes.Dup);
			ig.Emit (OpCodes.Ldtoken, fb);
			ig.Emit (OpCodes.Call,
				 TypeManager.void_initializearray_array_fieldhandle);
		}
		
		//
		// Emits pieces of the array that can not be computed at compile
		// time (variables and string locations).
		//
		// This always expect the top value on the stack to be the array
		//
		void EmitDynamicInitializers (EmitContext ec, bool is_expression)
		{
			ILGenerator ig = ec.ig;
			int dims = bounds.Count;
			int [] current_pos = new int [dims];
			int top = array_data.Count;
			LocalBuilder temp = ig.DeclareLocal (type);

			ig.Emit (OpCodes.Stloc, temp);

			MethodInfo set = null;

			if (dims != 1){
				Type [] args;
				ModuleBuilder mb = null;
				mb = CodeGen.ModuleBuilder;
				args = new Type [dims + 1];

				int j;
				for (j = 0; j < dims; j++)
					args [j] = TypeManager.int32_type;

				args [j] = array_element_type;
				
				set = mb.GetArrayMethod (
					type, "Set",
					CallingConventions.HasThis | CallingConventions.Standard,
					TypeManager.void_type, args);
			}
			
			for (int i = 0; i < top; i++){

				Expression e = null;

				if (array_data [i] is Expression)
					e = (Expression) array_data [i];

				if (e != null) {
					//
					// Basically we do this for string literals and
					// other non-literal expressions
					//
					if (e is StringConstant || !(e is Constant) ||
					    num_automatic_initializers <= 2) {
						Type etype = e.Type;
						
						ig.Emit (OpCodes.Ldloc, temp);

						for (int idx = 0; idx < dims; idx++) 
							IntConstant.EmitInt (ig, current_pos [idx]);

						//
						// If we are dealing with a struct, get the
						// address of it, so we can store it.
						//
						if ((dims == 1) &&
						    etype.IsSubclassOf (TypeManager.value_type) &&
						    (!TypeManager.IsBuiltinType (etype) ||
						     etype == TypeManager.decimal_type)) {
							if (e is New){
								New n = (New) e;

								//
								// Let new know that we are providing
								// the address where to store the results
								//
								n.DisableTemporaryValueType ();
							}
									     
							ig.Emit (OpCodes.Ldelema, etype);
						}

						e.Emit (ec);
						
						if (dims == 1)
							ArrayAccess.EmitStoreOpcode (ig, array_element_type);
						else 
							ig.Emit (OpCodes.Call, set);
					}
				}
				
				//
				// Advance counter
				//
				for (int j = dims - 1; j >= 0; j--){
					current_pos [j]++;
					if (current_pos [j] < (int) bounds [j])
						break;
					current_pos [j] = 0;
				}
			}

			if (is_expression)
				ig.Emit (OpCodes.Ldloc, temp);
		}

		void EmitArrayArguments (EmitContext ec)
		{
			ILGenerator ig = ec.ig;
			
			foreach (Argument a in arguments) {
				Type atype = a.Type;
				a.Emit (ec);

				if (atype == TypeManager.uint64_type)
					ig.Emit (OpCodes.Conv_Ovf_U4);
				else if (atype == TypeManager.int64_type)
					ig.Emit (OpCodes.Conv_Ovf_I4);
			}
		}
		
		void DoEmit (EmitContext ec, bool is_statement)
		{
			ILGenerator ig = ec.ig;
			
			EmitArrayArguments (ec);
			if (is_one_dimensional)
				ig.Emit (OpCodes.Newarr, array_element_type);
			else {
				if (is_builtin_type) 
					ig.Emit (OpCodes.Newobj, (ConstructorInfo) new_method);
				else 
					ig.Emit (OpCodes.Newobj, (MethodInfo) new_method);
			}
			
			if (initializers != null){
				//
				// FIXME: Set this variable correctly.
				// 
				bool dynamic_initializers = true;

				if (underlying_type != TypeManager.string_type &&
				    underlying_type != TypeManager.object_type) {
					if (num_automatic_initializers > 2)
						EmitStaticInitializers (ec, dynamic_initializers || !is_statement);
				}
				
				if (dynamic_initializers)
					EmitDynamicInitializers (ec, !is_statement);
			}
		}
		
		public override void Emit (EmitContext ec)
		{
			DoEmit (ec, false);
		}

		public override void EmitStatement (EmitContext ec)
		{
			DoEmit (ec, true);
		}
		
	}
	
	/// <summary>
	///   Represents the 'this' construct
	/// </summary>
	public class This : Expression, IAssignMethod, IMemoryLocation, IVariable {

		public enum TypeOfAccess : byte {
			Me, MyClass
		}

		Block block;
		VariableInfo vi;
		TypeOfAccess access_type;
		
		public This (TypeOfAccess access_type, Block block, Location loc)
		{
			this.loc = loc;
			this.block = block;
			this.access_type = access_type;
		}

		public This (Block block, Location loc)
		{
			this.loc = loc;
			this.block = block;
			this.access_type = TypeOfAccess.Me;
		}

		public This (Location loc)
		{
			this.loc = loc;
			this.access_type = TypeOfAccess.Me;
		}

		public TypeOfAccess AccessType { 
			get { return access_type; }
		}

		public bool IsAssigned (EmitContext ec, Location loc)
		{
			if (vi == null)
				return true;

			return vi.IsAssigned (ec, loc);
		}

		public bool IsFieldAssigned (EmitContext ec, string field_name, Location loc)
		{
			if (vi == null)
				return true;

			return vi.IsFieldAssigned (ec, field_name, loc);
		}

		public void SetAssigned (EmitContext ec)
		{
			if (vi != null)
				vi.SetAssigned (ec);
		}

		public void SetFieldAssigned (EmitContext ec, string field_name)
		{	
			if (vi != null)
				vi.SetFieldAssigned (ec, field_name);
		}

		public override Expression DoResolve (EmitContext ec)
		{
			eclass = ExprClass.Variable;
			type = ec.ContainerType;

			if (ec.IsStatic){
				Error (26, "Keyword this not valid in static code");
				return null;
			}

			if (block != null)
				vi = block.ThisVariable;

			return this;
		}

		override public Expression DoResolveLValue (EmitContext ec, Expression right_side)
		{
			DoResolve (ec);

			VariableInfo vi = ec.CurrentBlock.ThisVariable;
			if (vi != null)
				vi.SetAssigned (ec);
			
			if (ec.TypeContainer is Class){
				Error (1604, "Cannot assign to 'this'");
				return null;
			}

			return this;
		}

		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;
			
			ig.Emit (OpCodes.Ldarg_0);
			if (ec.TypeContainer is Struct)
				ig.Emit (OpCodes.Ldobj, type);
		}

		public void EmitAssign (EmitContext ec, Expression source)
		{
			ILGenerator ig = ec.ig;
			
			if (ec.TypeContainer is Struct){
				ig.Emit (OpCodes.Ldarg_0);
				source.Emit (ec);
				ig.Emit (OpCodes.Stobj, type);
			} else {
				source.Emit (ec);
				ig.Emit (OpCodes.Starg, 0);
			}
		}

		public void AddressOf (EmitContext ec, AddressOp mode)
		{
			ec.ig.Emit (OpCodes.Ldarg_0);

			// FIMXE
			// FIGURE OUT WHY LDARG_S does not work
			//
			// consider: struct X { int val; int P { set { val = value; }}}
			//
			// Yes, this looks very bad. Look at 'NOTAS' for
			// an explanation.
			// ec.ig.Emit (OpCodes.Ldarga_S, (byte) 0);
		}
	}

	/// <summary>
	///   Implements the typeof operator
	/// </summary>
	public class TypeOf : Expression {
		public readonly Expression QueriedType;
		Type typearg;
		
		public TypeOf (Expression queried_type, Location l)
		{
			QueriedType = queried_type;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			typearg = ec.DeclSpace.ResolveType (QueriedType, false, loc);

			if (typearg == null)
				return null;

			type = TypeManager.type_type;
			eclass = ExprClass.Type;
			return this;
		}

		public override void Emit (EmitContext ec)
		{
			ec.ig.Emit (OpCodes.Ldtoken, typearg);
			ec.ig.Emit (OpCodes.Call, TypeManager.system_type_get_type_from_handle);
		}

		public Type TypeArg { 
			get { return typearg; }
		}
	}

	/// <summary>
	///   Implements the sizeof expression
	/// </summary>
	public class SizeOf : Expression {
		public readonly Expression QueriedType;
		Type type_queried;
		
		public SizeOf (Expression queried_type, Location l)
		{
			this.QueriedType = queried_type;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			if (!ec.InUnsafe) {
				Error (233, "Sizeof may only be used in an unsafe context " +
				       "(consider using System.Runtime.InteropServices.Marshal.SizeOf");
				return null;
			}
				
			type_queried = ec.DeclSpace.ResolveType (QueriedType, false, loc);
			if (type_queried == null)
				return null;

			if (!TypeManager.IsUnmanagedType (type_queried)){
				Report.Error (208, "Cannot take the size of an unmanaged type (" + TypeManager.MonoBASIC_Name (type_queried) + ")");
				return null;
			}
			
			type = TypeManager.int32_type;
			eclass = ExprClass.Value;
			return this;
		}

		public override void Emit (EmitContext ec)
		{
			int size = GetTypeSize (type_queried);

			if (size == 0)
				ec.ig.Emit (OpCodes.Sizeof, type_queried);
			else
				IntConstant.EmitInt (ec.ig, size);
		}
	}

	/// <summary>
	///   Implements the member access expression
	/// </summary>
	public class MemberAccess : Expression, ITypeExpression {
		public readonly string Identifier;
		Expression expr;
		Expression member_lookup;
		bool is_invocation;
		bool is_left_hand;
		
		public MemberAccess (Expression expr, string id, Location l)
		{
			this.expr = expr;
			Identifier = id;
			loc = l;
		}

		public MemberAccess (Expression expr, string id, Location l, bool isInvocation)
		{
			this.expr = expr;
			Identifier = id;
			loc = l;
			is_invocation = isInvocation;
		}

		public bool IsInvocation {
			get {
				return is_invocation;
			}
			set {
				is_invocation = value;
			}
		}

		public bool IsLeftHand {
			get {
				return is_left_hand;
			}
			set {
				is_left_hand = value;
			}
		}

		public Expression Expr {
			get {
				return expr;
			}
		}

		static void error176 (Location loc, string name)
		{
			Report.Error (176, loc, "Static member '" +
				      name + "' cannot be accessed " +
				      "with an instance reference, qualify with a " +
				      "type name instead");
		}

		static bool IdenticalNameAndTypeName (EmitContext ec, Expression left_original, Location loc)
		{
			if (left_original == null)
				return false;

			if (!(left_original is SimpleName))
				return false;

			SimpleName sn = (SimpleName) left_original;

			Type t = RootContext.LookupType (ec.DeclSpace, sn.Name, true, loc);
			if (t != null)
				return true;

			return false;
		}
		
		public static Expression ResolveMemberAccess (EmitContext ec, Expression member_lookup,
							      Expression left, Location loc,
							      Expression left_original)
		{
			 bool left_is_type, left_is_explicit;
			

			// If 'left' is null, then we're called from SimpleNameResolve and this is
			// a member in the currently defining class.
			if (left == null) {
				left_is_type = ec.IsStatic || ec.IsFieldInitializer;
				left_is_explicit = false;

				// Implicitly default to 'this' unless we're static.
				if (!ec.IsStatic && !ec.IsFieldInitializer && !ec.InEnumContext)
					left = ec.This;
			} else {
				left_is_type = left is TypeExpr;
				left_is_explicit = true;
			}

			if (member_lookup is FieldExpr){
				FieldExpr fe = (FieldExpr) member_lookup;
				FieldInfo fi = fe.FieldInfo;
				Type decl_type = fi.DeclaringType;
				
				if (fi is FieldBuilder) {
					Const c = TypeManager.LookupConstant ((FieldBuilder) fi);
					if (c != null) {
                                        object o;
                                        if (!c.LookupConstantValue (out o, ec))
                                                return null;
					
						object real_value = ((Constant) c.Expr).GetValue ();
                                         Expression exp = Constantify (real_value, fi.FieldType);

                                        return exp;
                                	}
				}
				
				  // IsInitOnly is because of MS compatibility, I don't know why but they emit decimal constant as InitOnly
                        
			if (fi.IsInitOnly && !(fi is FieldBuilder) && fi.FieldType == TypeManager.decimal_type) {
                                object[] attrs = fi.GetCustomAttributes (TypeManager.decimal_constant_attribute_type, false);
                                if (attrs.Length == 1)
                                        return new DecimalConstant (((System.Runtime.CompilerServices.DecimalConstantAttribute) attrs [0]).Value);
                        }



				if (fi.IsLiteral) {
					Type t = fi.FieldType;
					
					object o;

					if (fi is FieldBuilder)
						o = TypeManager.GetValue ((FieldBuilder) fi);
					else
						o = fi.GetValue (fi);
					
					if (decl_type.IsSubclassOf (TypeManager.enum_type)) {
						if (left_is_explicit && !left_is_type &&
						    !IdenticalNameAndTypeName (ec, left_original, loc)) {
							error176 (loc, fe.FieldInfo.Name);
							return null;
						}					
						
						Expression enum_member = MemberLookup (
							ec, decl_type, "value__", MemberTypes.Field,
							AllBindingFlags, loc); 

						Enum en = TypeManager.LookupEnum (decl_type);

						Constant c;
						if (en != null)
							c = Constantify (o, en.UnderlyingType);
						else
							c = Constantify (o, enum_member.Type);

						return new EnumConstant (c, decl_type);
					}
					
					Expression exp = Constantify (o, t);

					if (left_is_explicit && !left_is_type) {
						error176 (loc, fe.FieldInfo.Name);
						return null;
					}
					
					return exp;
				}

				if (fi.FieldType.IsPointer && !ec.InUnsafe){
					UnsafeError (loc);
					return null;
				}
			}

			
			if (member_lookup is IMemberExpr) {
				IMemberExpr me = (IMemberExpr) member_lookup;

				if (left_is_type){
					MethodGroupExpr mg = me as MethodGroupExpr;
					if ((mg != null) && left_is_explicit && left.Type.IsInterface)
						mg.IsExplicitImpl = left_is_explicit;

					if (!me.IsStatic){
						if (IdenticalNameAndTypeName (ec, left_original, loc))
							return member_lookup;

						SimpleName.Error_ObjectRefRequired (ec, loc, me.Name);
						return null;
					}

				} else {
					if (!me.IsInstance){
						if (IdenticalNameAndTypeName (ec, left_original, loc))
							return member_lookup;

						/*if (left_is_explicit) {
							error176 (loc, me.Name);
							return null;
						}*/
					}

					//
					// Since we can not check for instance objects in SimpleName,
					// becaue of the rule that allows types and variables to share
					// the name (as long as they can be de-ambiguated later, see 
					// IdenticalNameAndTypeName), we have to check whether left 
					// is an instance variable in a static context
					//
					// However, if the left-hand value is explicitly given, then
					// it is already our instance expression, so we aren't in
					// static context.
					//

					if (ec.IsStatic && !left_is_explicit && left is IMemberExpr){
						IMemberExpr mexp = (IMemberExpr) left;

						if (!mexp.IsStatic){
							SimpleName.Error_ObjectRefRequired (ec, loc, mexp.Name);
							return null;
						}
					}

					me.InstanceExpression = left;
				}

				return member_lookup;
			}

			if (member_lookup is TypeExpr){
				member_lookup.Resolve (ec, ResolveFlags.Type);
				return member_lookup;
			}
			
			Console.WriteLine ("Left is: " + left);
			Report.Error (-100, loc, "Support for [" + member_lookup + "] is not present yet");
			Environment.Exit (0);
			return null;
		}
		
		public Expression DoResolve (EmitContext ec, Expression right_side, ResolveFlags flags)
		{
			if (type != null)
				throw new Exception ();
			//
			// Resolve the expression with flow analysis turned off, we'll do the definite
			// assignment checks later.  This is because we don't know yet what the expression
			// will resolve to - it may resolve to a FieldExpr and in this case we must do the
			// definite assignment check on the actual field and not on the whole struct.
			//

			Expression original = expr;
			expr = expr.Resolve (ec, flags | ResolveFlags.DisableFlowAnalysis);
			
			if (expr == null)
				return null;

			if (expr is SimpleName){
				SimpleName child_expr = (SimpleName) expr;

				Expression new_expr = new SimpleName (child_expr.Name + "." + Identifier, loc);

				if ((flags & ResolveFlags.MaskExprClass) == ResolveFlags.Type)
					return new_expr.Resolve (ec, flags);
				else
					return new_expr.Resolve (ec, flags | ResolveFlags.MethodGroup | ResolveFlags.VariableOrValue);
			}
					
			int errors = Report.Errors;
			
			Type expr_type = expr.Type;

			if (expr is TypeExpr){
				//FIXME: add access level check
				//if (!ec.DeclSpace.CheckAccessLevel (expr_type)) {
				//		Error (30390, "'" + TypeManager.MonoBASIC_Name (expr_type) + "' " +
				//		       "is inaccessible because of its protection level");
				//	return null;
				//}

				if (expr_type == TypeManager.enum_type || expr_type.IsSubclassOf (TypeManager.enum_type)){
					Enum en = TypeManager.LookupEnum (expr_type);

					if (en != null) {
						object value = en.LookupEnumValue (Identifier);
						
						if (value != null){
							Constant c = Constantify (value, en.UnderlyingType);
							return new EnumConstant (c, expr_type);
						} else {
							Report.Error (30456, loc,
								Identifier + " is not found in member list of enum " + en.Name);
						}
					}
				}
			}
			
			if (expr_type.IsPointer){
				Error (30311, "The '.' operator can not be applied to pointer operands (" +
				       TypeManager.MonoBASIC_Name (expr_type) + ")");
				return null;
			}

			member_lookup = MemberLookup (ec, expr_type, Identifier, loc);

			if (member_lookup == null)
			{
				// Error has already been reported.
				if (errors < Report.Errors)
					return null;
				
				//
				// Try looking the member up from the same type, if we find
				// it, we know that the error was due to limited visibility
				//
				object lookup = TypeManager.MemberLookup (
					expr_type, expr_type, AllMemberTypes, AllBindingFlags |
					BindingFlags.NonPublic, Identifier);
					
				if (lookup == null) {
					if (expr_type != TypeManager.object_type)
						Error (30456, "'" + expr_type + "' does not contain a definition for '" + Identifier + "'");
					// If this came as a part of Invocation, 
					// Since argumets are not known, return null, 
					// let Invocation's Resolve take care
					if (is_invocation)
						return null;

					else if (! is_left_hand) {
						StatementSequence etmp = new StatementSequence (ec.CurrentBlock, 
										loc, this, null, 
										true, is_left_hand);
						etmp.GenerateLateBindingStatements();
						return etmp.Resolve (ec);
					} 

					// if the expression is a left hand side of an assignment,
					// return null, as we dont know the RHS
					// Let assign take care of Late Binding
					return null;
				}
				else
				{
					if ((expr_type != ec.ContainerType) &&
						 ec.ContainerType.IsSubclassOf (expr_type))
					{

						// Although a derived class can access protected members of
						// its base class it cannot do so through an instance of the
						// base class (CS1540).  If the expr_type is a parent of the
						// ec.ContainerType and the lookup succeeds with the latter one,
						// then we are in this situation.

						lookup = TypeManager.MemberLookup(
									ec.ContainerType, ec.ContainerType, AllMemberTypes, 
									AllBindingFlags, Identifier);

						if (lookup != null)
							Error (1540, "Cannot access protected member '" +
						       expr_type + "." + Identifier + "' " +
						       "via a qualifier of type '" + TypeManager.MonoBASIC_Name (expr_type) + "'; the " +
						       "qualifier must be of type '" + TypeManager.MonoBASIC_Name (ec.ContainerType) + "' " +
						       "(or derived from it)");
						else
							Error (30390, "'" + expr_type + "." + Identifier + "' " +
						       "is inaccessible because of its protection level");
					} else
						Error (30390, "'" + expr_type + "." + Identifier + "' " +
					       "is inaccessible because of its protection level");
				}  
				return null;
			}

			if ((expr is TypeExpr) && (expr_type.IsSubclassOf (TypeManager.enum_type)))	{
				Enum en = TypeManager.LookupEnum (expr_type);
				
				if (en != null) {
					object value = en.LookupEnumValue (Identifier);
					expr_type = TypeManager.int32_type;
					if (value != null) {
						Constant c = Constantify (value, en.UnderlyingType);
						return new EnumConstant (c, en.UnderlyingType);
					} else {
						Report.Error (30456, loc,
							Identifier + " is not found in member list of enum " + en.Name);
					}
				}
			}

			if (member_lookup is TypeExpr){
				member_lookup.Resolve (ec, ResolveFlags.Type);

				return member_lookup;
			} else if ((flags & ResolveFlags.MaskExprClass) == ResolveFlags.Type)
				return null;
			
			member_lookup = ResolveMemberAccess (ec, member_lookup, expr, loc, original);
			if (member_lookup == null)
				return null;

			// The following DoResolve/DoResolveLValue will do the definite assignment
			// check.
			if (right_side != null)
				member_lookup = member_lookup.DoResolveLValue (ec, right_side);
			else
				member_lookup = member_lookup.DoResolve (ec);

			return member_lookup;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			return DoResolve (ec, null, ResolveFlags.VariableOrValue |
					  ResolveFlags.SimpleName | ResolveFlags.Type);
		}

		public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
		{
			return DoResolve (ec, right_side, ResolveFlags.VariableOrValue |
					  ResolveFlags.SimpleName | ResolveFlags.Type);
		}

		public Expression DoResolveType (EmitContext ec)
		{
			return DoResolve (ec, null, ResolveFlags.Type);
		}

		public override void Emit (EmitContext ec)
		{
			throw new Exception ("Should not happen");
		}

		public override string ToString ()
		{
			return expr + "." + Identifier;
		}
	}

	
	
	/// <summary>
	///   Implements checked expressions
	/// </summary>
	public class CheckedExpr : Expression {

		public Expression Expr;

		public CheckedExpr (Expression e, Location l)
		{
			Expr = e;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			bool last_const_check = ec.ConstantCheckState;

			ec.ConstantCheckState = true;
			Expr = Expr.Resolve (ec);
			ec.ConstantCheckState = last_const_check;
			
			if (Expr == null)
				return null;

			if (Expr is Constant)
				return Expr;
			
			eclass = Expr.eclass;
			type = Expr.Type;
			return this;
		}

		public override void Emit (EmitContext ec)
		{
			bool last_check = ec.CheckState;
			bool last_const_check = ec.ConstantCheckState;
			
			ec.CheckState = true;
			ec.ConstantCheckState = true;
			Expr.Emit (ec);
			ec.CheckState = last_check;
			ec.ConstantCheckState = last_const_check;
		}
		
	}

	/// <summary>
	///   Implements the unchecked expression
	/// </summary>
	public class UnCheckedExpr : Expression {

		public Expression Expr;

		public UnCheckedExpr (Expression e, Location l)
		{
			Expr = e;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			bool last_const_check = ec.ConstantCheckState;

			ec.ConstantCheckState = false;
			Expr = Expr.Resolve (ec);
			ec.ConstantCheckState = last_const_check;

			if (Expr == null)
				return null;

			if (Expr is Constant)
				return Expr;
			
			eclass = Expr.eclass;
			type = Expr.Type;
			return this;
		}

		public override void Emit (EmitContext ec)
		{
			bool last_check = ec.CheckState;
			bool last_const_check = ec.ConstantCheckState;
			
			ec.CheckState = false;
			ec.ConstantCheckState = false;
			Expr.Emit (ec);
			ec.CheckState = last_check;
			ec.ConstantCheckState = last_const_check;
		}
		
	}

	/// <summary>
	///   An Element Access expression.
	///
	///   During semantic analysis these are transformed into 
	///   IndexerAccess or ArrayAccess 
	/// </summary>
	public class ElementAccess : Expression {
		public ArrayList  Arguments;
		public Expression Expr;
		
		public ElementAccess (Expression e, ArrayList e_list, Location l)
		{
			Expr = e;

			loc  = l;
			
			if (e_list == null)
				return;
			
			Arguments = new ArrayList ();
			foreach (Expression tmp in e_list)
				Arguments.Add (new Argument (tmp, Argument.AType.Expression));
			
		}

		bool CommonResolve (EmitContext ec)
		{
			Expr = Expr.Resolve (ec);

			if (Expr == null) 
				return false;

			if (Arguments == null)
				return false;

			foreach (Argument a in Arguments){
				if (!a.Resolve (ec, loc))
					return false;
			}

			return true;
		}

		Expression MakePointerAccess ()
		{
			Type t = Expr.Type;

			if (t == TypeManager.void_ptr_type){
				Error (
					242,
					"The array index operation is not valid for void pointers");
				return null;
			}
			if (Arguments.Count != 1){
				Error (
					196,
					"A pointer must be indexed by a single value");
				return null;
			}
			Expression p = new PointerArithmetic (true, Expr, ((Argument)Arguments [0]).Expr,
							      t, loc);
			return new Indirection (p, loc);
		}
		
		public override Expression DoResolve (EmitContext ec)
		{
			if (!CommonResolve (ec))
				return null;

			//
			// We perform some simple tests, and then to "split" the emit and store
			// code we create an instance of a different class, and return that.
			//
			// I am experimenting with this pattern.
			//
			Type t = Expr.Type;

			if (t.IsArray)
				return (new ArrayAccess (this, loc)).Resolve (ec);
			else if (t.IsPointer)
				return MakePointerAccess ();
			else
				return (new IndexerAccess (this, loc)).Resolve (ec);
		}

		public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
		{
			if (!CommonResolve (ec))
				return null;

			Type t = Expr.Type;
			if (t.IsArray)
				return (new ArrayAccess (this, loc)).ResolveLValue (ec, right_side);
			else if (t.IsPointer)
				return MakePointerAccess ();
			else
				return (new IndexerAccess (this, loc)).ResolveLValue (ec, right_side);
		}
		
		public override void Emit (EmitContext ec)
		{
			throw new Exception ("Should never be reached");
		}
	}

	/// <summary>
	///   Implements array access 
	/// </summary>
	public class ArrayAccess : Expression, IAssignMethod, IMemoryLocation {
		//
		// Points to our "data" repository
		//
		ElementAccess ea;

		LocalTemporary [] cached_locations;

		public ArrayAccess (ElementAccess ea_data, Location l)
		{
			ea = ea_data;
			eclass = ExprClass.Variable;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			//ExprClass eclass = ea.Expr.eclass;

#if false
			// As long as the type is valid
			if (!(eclass == ExprClass.Variable || eclass == ExprClass.PropertyAccess ||
			      eclass == ExprClass.Value)) {
				ea.Expr.Error118 ("variable or value");
				return null;
			}
#endif

			Type t = ea.Expr.Type;
/*
			if (t == typeof (System.Object))
			{
				// We can't resolve now, but we
				// have to try to access the array with a call
				// to LateIndexGet in the runtime

				Expression lig_call_expr = Mono.MonoBASIC.Parser.DecomposeQI("Microsoft.VisualBasic.CompilerServices.LateBinding.LateIndexGet", Location.Null);
				Expression obj_type = Mono.MonoBASIC.Parser.DecomposeQI("System.Object", Location.Null);
				ArrayList adims = new ArrayList();

				ArrayList ainit = new ArrayList();
				foreach (Argument a in ea.Arguments)
					ainit.Add ((Expression) a.Expr);

				adims.Add ((Expression) new IntLiteral (ea.Arguments.Count));

				Expression oace = new ArrayCreation (obj_type, adims, "", ainit, Location.Null);

				ArrayList args = new ArrayList();
				args.Add (new Argument(ea.Expr, Argument.AType.Expression));
				args.Add (new Argument(oace, Argument.AType.Expression));
				args.Add (new Argument(NullLiteral.Null, Argument.AType.Expression));

				Expression lig_call = new Invocation (lig_call_expr, args, Location.Null);
				lig_call = lig_call.Resolve(ec);
				return lig_call;
			}
*/
			if (t.GetArrayRank () != ea.Arguments.Count){
				ea.Error (22,
					  "Incorrect number of indexes for array " +
					  " expected: " + t.GetArrayRank () + " got: " +
					  ea.Arguments.Count);
				return null;
			}
			type = TypeManager.TypeToCoreType (t.GetElementType ());
			if (type.IsPointer && !ec.InUnsafe){
				UnsafeError (ea.Location);
				return null;
			}

			foreach (Argument a in ea.Arguments){
				Type argtype = a.Type;

				if (argtype == TypeManager.int32_type ||
				    argtype == TypeManager.uint32_type ||
				    argtype == TypeManager.int64_type ||
				    argtype == TypeManager.uint64_type)
					continue;

				//
				// Mhm.  This is strage, because the Argument.Type is not the same as
				// Argument.Expr.Type: the value changes depending on the ref/out setting.
				//
				// Wonder if I will run into trouble for this.
				//
				a.Expr = ExpressionToArrayArgument (ec, a.Expr, ea.Location);
				if (a.Expr == null)
					return null;
			}
			
			eclass = ExprClass.Variable;

			return this;
		}

		/// <summary>
		///    Emits the right opcode to load an object of Type 't'
		///    from an array of T
		/// </summary>
		static public void EmitLoadOpcode (ILGenerator ig, Type type)
		{
			if (type == TypeManager.byte_type || type == TypeManager.bool_type)
				ig.Emit (OpCodes.Ldelem_U1);
			else if (type == TypeManager.sbyte_type)
				ig.Emit (OpCodes.Ldelem_I1);
			else if (type == TypeManager.short_type)
				ig.Emit (OpCodes.Ldelem_I2);
			else if (type == TypeManager.ushort_type || type == TypeManager.char_type)
				ig.Emit (OpCodes.Ldelem_U2);
			else if (type == TypeManager.int32_type)
				ig.Emit (OpCodes.Ldelem_I4);
			else if (type == TypeManager.uint32_type)
				ig.Emit (OpCodes.Ldelem_U4);
			else if (type == TypeManager.uint64_type)
				ig.Emit (OpCodes.Ldelem_I8);
			else if (type == TypeManager.int64_type)
				ig.Emit (OpCodes.Ldelem_I8);
			else if (type == TypeManager.float_type)
				ig.Emit (OpCodes.Ldelem_R4);
			else if (type == TypeManager.double_type)
				ig.Emit (OpCodes.Ldelem_R8);
			else if (type == TypeManager.intptr_type)
				ig.Emit (OpCodes.Ldelem_I);
			else if (type.IsValueType){
				ig.Emit (OpCodes.Ldelema, type);
				ig.Emit (OpCodes.Ldobj, type);
			} else 
				ig.Emit (OpCodes.Ldelem_Ref);
		}

		/// <summary>
		///    Emits the right opcode to store an object of Type 't'
		///    from an array of T.  
		/// </summary>
		static public void EmitStoreOpcode (ILGenerator ig, Type t)
		{
			t = TypeManager.TypeToCoreType (t);
			if (TypeManager.IsEnumType (t) && t != TypeManager.enum_type)
				t = TypeManager.EnumToUnderlying (t);
			if (t == TypeManager.byte_type || t == TypeManager.sbyte_type ||
			    t == TypeManager.bool_type)
				ig.Emit (OpCodes.Stelem_I1);
			else if (t == TypeManager.short_type || t == TypeManager.ushort_type || t == TypeManager.char_type)
				ig.Emit (OpCodes.Stelem_I2);
			else if (t == TypeManager.int32_type || t == TypeManager.uint32_type)
				ig.Emit (OpCodes.Stelem_I4);
			else if (t == TypeManager.int64_type || t == TypeManager.uint64_type)
				ig.Emit (OpCodes.Stelem_I8);
			else if (t == TypeManager.float_type)
				ig.Emit (OpCodes.Stelem_R4);
			else if (t == TypeManager.double_type)
				ig.Emit (OpCodes.Stelem_R8);
			else if (t == TypeManager.intptr_type)
				ig.Emit (OpCodes.Stelem_I);
			else if (t.IsValueType){
				ig.Emit (OpCodes.Stobj, t);
			} else
				ig.Emit (OpCodes.Stelem_Ref);
		}

		MethodInfo FetchGetMethod ()
		{
			ModuleBuilder mb = CodeGen.ModuleBuilder;
			int arg_count = ea.Arguments.Count;
			Type [] args = new Type [arg_count];
			MethodInfo get;
			
			for (int i = 0; i < arg_count; i++){
				//args [i++] = a.Type;
				args [i] = TypeManager.int32_type;
			}
			
			get = mb.GetArrayMethod (
				ea.Expr.Type, "Get",
				CallingConventions.HasThis |
				CallingConventions.Standard,
				type, args);
			return get;
		}
				

		MethodInfo FetchAddressMethod ()
		{
			ModuleBuilder mb = CodeGen.ModuleBuilder;
			int arg_count = ea.Arguments.Count;
			Type [] args = new Type [arg_count];
			MethodInfo address;
			string ptr_type_name;
			Type ret_type;
			
			ptr_type_name = type.FullName + "&";
			ret_type = Type.GetType (ptr_type_name);
			
			//
			// It is a type defined by the source code we are compiling
			//
			if (ret_type == null){
				ret_type = mb.GetType (ptr_type_name);
			}

			for (int i = 0; i < arg_count; i++){
				//args [i++] = a.Type;
				args [i] = TypeManager.int32_type;
			}
			
			address = mb.GetArrayMethod (
				ea.Expr.Type, "Address",
				CallingConventions.HasThis |
				CallingConventions.Standard,
				ret_type, args);

			return address;
		}

		//
		// Load the array arguments into the stack.
		//
		// If we have been requested to cache the values (cached_locations array
		// initialized), then load the arguments the first time and store them
		// in locals.  otherwise load from local variables.
		//
		void LoadArrayAndArguments (EmitContext ec)
		{
			ILGenerator ig = ec.ig;
			
			if (cached_locations == null){
				ea.Expr.Emit (ec);
				foreach (Argument a in ea.Arguments){
					Type argtype = a.Expr.Type;
					
					a.Expr.Emit (ec);
					
					if (argtype == TypeManager.int64_type)
						ig.Emit (OpCodes.Conv_Ovf_I);
					else if (argtype == TypeManager.uint64_type)
						ig.Emit (OpCodes.Conv_Ovf_I_Un);
				}
				return;
			}

			if (cached_locations [0] == null){
				cached_locations [0] = new LocalTemporary (ec, ea.Expr.Type);
				ea.Expr.Emit (ec);
				ig.Emit (OpCodes.Dup);
				cached_locations [0].Store (ec);
				
				int j = 1;
				
				foreach (Argument a in ea.Arguments){
					Type argtype = a.Expr.Type;
					
					cached_locations [j] = new LocalTemporary (ec, TypeManager.intptr_type /* a.Expr.Type */);
					a.Expr.Emit (ec);
					if (argtype == TypeManager.int64_type)
						ig.Emit (OpCodes.Conv_Ovf_I);
					else if (argtype == TypeManager.uint64_type)
						ig.Emit (OpCodes.Conv_Ovf_I_Un);

					ig.Emit (OpCodes.Dup);
					cached_locations [j].Store (ec);
					j++;
				}
				return;
			}

			foreach (LocalTemporary lt in cached_locations)
				lt.Emit (ec);
		}

		public new void CacheTemporaries (EmitContext ec)
		{
			cached_locations = new LocalTemporary [ea.Arguments.Count + 1];
		}
		
		public override void Emit (EmitContext ec)
		{
			int rank = ea.Expr.Type.GetArrayRank ();
			ILGenerator ig = ec.ig;

			LoadArrayAndArguments (ec);
			
			if (rank == 1)
				EmitLoadOpcode (ig, type);
			else {
				MethodInfo method;
				
				method = FetchGetMethod ();
				ig.Emit (OpCodes.Call, method);
			}
		}

		public void EmitAssign (EmitContext ec, Expression source)
		{
			int rank = ea.Expr.Type.GetArrayRank ();
			ILGenerator ig = ec.ig;
			Type t = source.Type;

			LoadArrayAndArguments (ec);

			//
			// The stobj opcode used by value types will need
			// an address on the stack, not really an array/array
			// pair
			//
			if (rank == 1){
				if (t == TypeManager.enum_type || t == TypeManager.decimal_type ||
				    (t.IsSubclassOf (TypeManager.value_type) && !TypeManager.IsEnumType (t) && !TypeManager.IsBuiltinType (t)))
					ig.Emit (OpCodes.Ldelema, t);
			}
			
			source.Emit (ec);

			if (rank == 1)
				EmitStoreOpcode (ig, t);
			else {
				ModuleBuilder mb = CodeGen.ModuleBuilder;
				int arg_count = ea.Arguments.Count;
				Type [] args = new Type [arg_count + 1];
				MethodInfo set;
				
				for (int i = 0; i < arg_count; i++){
					//args [i++] = a.Type;
					args [i] = TypeManager.int32_type;
				}

				args [arg_count] = type;
				
				set = mb.GetArrayMethod (
					ea.Expr.Type, "Set",
					CallingConventions.HasThis |
					CallingConventions.Standard,
					TypeManager.void_type, args);
				
				ig.Emit (OpCodes.Call, set);
			}
		}

		public void AddressOf (EmitContext ec, AddressOp mode)
		{
			int rank = ea.Expr.Type.GetArrayRank ();
			ILGenerator ig = ec.ig;

			LoadArrayAndArguments (ec);

			if (rank == 1){
				ig.Emit (OpCodes.Ldelema, type);
			} else {
				MethodInfo address = FetchAddressMethod ();
				ig.Emit (OpCodes.Call, address);
			}
		}
	}

	
	class Indexers {
		public ArrayList getters, setters;
		static Hashtable map;

		static Indexers ()
		{
			map = new Hashtable ();
		}

		Indexers (MemberInfo [] mi)
		{
			foreach (PropertyInfo property in mi){
				MethodInfo get, set;
				
				get = property.GetGetMethod (true);
				if (get != null){
					if (getters == null)
						getters = new ArrayList ();

					getters.Add (get);
				}
				
				set = property.GetSetMethod (true);
				if (set != null){
					if (setters == null)
						setters = new ArrayList ();
					setters.Add (set);
				}
			}
		}

		static private Indexers GetIndexersForTypeOrInterface (Type caller_type, Type lookup_type)
		{
			Indexers ix = (Indexers) map [lookup_type];
			
			if (ix != null)
				return ix;

			string p_name = TypeManager.IndexerPropertyName (lookup_type);

			MemberInfo [] mi = TypeManager.MemberLookup (
				caller_type, lookup_type, MemberTypes.Property,
				BindingFlags.Public | BindingFlags.Instance, p_name);

			if (mi == null || mi.Length == 0)
				return null;

			ix = new Indexers (mi);
			map [lookup_type] = ix;

			return ix;
		}
		
		static public Indexers GetIndexersForType (Type caller_type, Type lookup_type, Location loc) 
		{
			Indexers ix = (Indexers) map [lookup_type];
			
			if (ix != null)
				return ix;

			ix = GetIndexersForTypeOrInterface (caller_type, lookup_type);
			if (ix != null)
				return ix;

			Type [] ifaces = TypeManager.GetInterfaces (lookup_type);
			if (ifaces != null) {
				foreach (Type itype in ifaces) {
					ix = GetIndexersForTypeOrInterface (caller_type, itype);
					if (ix != null)
						return ix;
				}
			}

			if (lookup_type != TypeManager.object_type)
				Report.Error (21, loc,
					      "Type '" + TypeManager.MonoBASIC_Name (lookup_type) +
					      "' does not have any indexers defined");
			return null;
		}
	}

	/// <summary>
	///   Expressions that represent an indexer call.
	/// </summary>
	public class IndexerAccess : Expression, IAssignMethod {
		//
		// Points to our "data" repository
		//
		MethodInfo get, set;
		Indexers ilist;
		ArrayList set_arguments;
		//bool is_base_indexer;

		protected Type indexer_type;
		protected Type current_type;
		protected Expression instance_expr;
		protected ArrayList arguments;
		
		public IndexerAccess (ElementAccess ea, Location loc)
			: this (ea.Expr, false, loc)
		{
			this.arguments = ea.Arguments;
		}

		protected IndexerAccess (Expression instance_expr, bool is_base_indexer,
					 Location loc)
		{
			this.instance_expr = instance_expr;
			//this.is_base_indexer = is_base_indexer;
			this.eclass = ExprClass.Value;
			this.loc = loc;
		}

		public Expression Instance {
			get {
				return instance_expr;
			}
		}

		public ArrayList Arguments {
			get {
				return arguments;
			}
		}

		protected virtual bool CommonResolve (EmitContext ec)
		{
			indexer_type = instance_expr.Type;
			current_type = ec.ContainerType;

			return true;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			if (!CommonResolve (ec))
				return null;

			//
			// Step 1: Query for all 'Item' *properties*.  Notice
			// that the actual methods are pointed from here.
			//
			// This is a group of properties, piles of them.  

			if (ilist == null)
				ilist = Indexers.GetIndexersForType (
					current_type, indexer_type, loc);

			//
			// Step 2: find the proper match
			//
			if (ilist != null && ilist.getters != null && ilist.getters.Count > 0)
				get = (MethodInfo) Invocation.OverloadResolve (
					ec, new MethodGroupExpr (ilist.getters, loc), arguments, loc);

			if (get == null){
				if (instance_expr.Type != TypeManager.object_type)
					Error (30524, "indexer can not be used in this context, because " +
				   		"it lacks a 'get' accessor");
				return null;
			}

			type = get.ReturnType;
			if (type.IsPointer && !ec.InUnsafe){
				UnsafeError (loc);
				return null;
			}
			
			eclass = ExprClass.IndexerAccess;
			return this;
		}

		public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
		{
			if (!CommonResolve (ec))
				return null;

			Type right_type = right_side.Type;

			if (ilist == null)
				ilist = Indexers.GetIndexersForType (
					current_type, indexer_type, loc);

			if (ilist != null && ilist.setters != null && ilist.setters.Count > 0){
				set_arguments = (ArrayList) arguments.Clone ();
				set_arguments.Add (new Argument (right_side, Argument.AType.Expression));

				set = (MethodInfo) Invocation.OverloadResolve (
					ec, new MethodGroupExpr (ilist.setters, loc), set_arguments, loc);
			}
			
			if (set == null){
				Error (30526, "indexer X.this [" + TypeManager.MonoBASIC_Name (right_type) +
				       "] lacks a 'set' accessor");
				return null;
			}

			type = TypeManager.void_type;
			eclass = ExprClass.IndexerAccess;
			return this;
		}
		
		public override void Emit (EmitContext ec)
		{
			Invocation.EmitCall (ec, false, false, instance_expr, get, arguments, loc);
		}

		//
		// source is ignored, because we already have a copy of it from the
		// LValue resolution and we have already constructed a pre-cached
		// version of the arguments (ea.set_arguments);
		//
		public void EmitAssign (EmitContext ec, Expression source)
		{
			Invocation.EmitCall (ec, false, false, instance_expr, set, set_arguments, loc);
		}
	}

	/// <summary>
	///   The base operator for method names
	/// </summary>
	public class BaseAccess : Expression {
		public string member;
		
		public BaseAccess (string member, Location l)
		{
			this.member = member;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			Expression member_lookup;
			Type current_type = ec.ContainerType;
			Type base_type = current_type.BaseType;
			Expression e;

			if (ec.IsStatic){
				Error (1511, "Keyword MyBase is not allowed in static method");
				return null;
			}
			
			if (member == "New")
				member = ".ctor";
			
			member_lookup = MemberLookup (ec, current_type, base_type, member,
						      AllMemberTypes, AllBindingFlags, loc);

			if (member_lookup == null) {
				Error (30456,
					      TypeManager.MonoBASIC_Name (base_type) + " does not " +
					      "contain a definition for '" + member + "'");
				return null;
			}

			Expression left;
			
			if (ec.IsStatic)
				left = new TypeExpr (base_type, loc);
			else
				left = ec.This;
			
			e = MemberAccess.ResolveMemberAccess (ec, member_lookup, left, loc, null);

			if (e is PropertyExpr) {
				PropertyExpr pe = (PropertyExpr) e;

				pe.IsBase = true;
			}

			return e;
		}

		public override void Emit (EmitContext ec)
		{
			throw new Exception ("Should never be called"); 
		}
	}

	/// <summary>
	///   The base indexer operator
	/// </summary>
	public class BaseIndexerAccess : IndexerAccess {
		public BaseIndexerAccess (ArrayList args, Location loc)
			: base (null, true, loc)
		{
			arguments = new ArrayList ();
			foreach (Expression tmp in args)
				arguments.Add (new Argument (tmp, Argument.AType.Expression));
		}

		protected override bool CommonResolve (EmitContext ec)
		{
			instance_expr = ec.This;

			current_type = ec.ContainerType.BaseType;
			indexer_type = current_type;

			foreach (Argument a in arguments){
				if (!a.Resolve (ec, loc))
					return false;
			}

			return true;
		}
	}
	
	/// <summary>
	///   This class exists solely to pass the Type around and to be a dummy
	///   that can be passed to the conversion functions (this is used by
	///   foreach implementation to typecast the object return value from
	///   get_Current into the proper type.  All code has been generated and
	///   we only care about the side effect conversions to be performed
	///
	///   This is also now used as a placeholder where a no-action expression
	///   is needed (the 'New' class).
	/// </summary>
	public class EmptyExpression : Expression {
		public EmptyExpression ()
		{
			type = TypeManager.object_type;
			eclass = ExprClass.Value;
			loc = Location.Null;
		}

		public EmptyExpression (Type t)
		{
			type = t;
			eclass = ExprClass.Value;
			loc = Location.Null;
		}
		
		public override Expression DoResolve (EmitContext ec)
		{
			return this;
		}

		public override void Emit (EmitContext ec)
		{
			// nothing, as we only exist to not do anything.
		}

		//
		// This is just because we might want to reuse this bad boy
		// instead of creating gazillions of EmptyExpressions.
		// (CanConvertImplicit uses it)
		//
		public void SetType (Type t)
		{
			type = t;
		}
	}

	public class UserCast : Expression {
		MethodBase method;
		Expression source;
		
		public UserCast (MethodInfo method, Expression source, Location l)
		{
			this.method = method;
			this.source = source;
			type = method.ReturnType;
			eclass = ExprClass.Value;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			//
			// We are born fully resolved
			//
			return this;
		}

		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;

			source.Emit (ec);
			
			if (method is MethodInfo)
				ig.Emit (OpCodes.Call, (MethodInfo) method);
			else
				ig.Emit (OpCodes.Call, (ConstructorInfo) method);

		}
	}

	// <summary>
	//   This class is used to "construct" the type during a typecast
	//   operation.  Since the Type.GetType class in .NET can parse
	//   the type specification, we just use this to construct the type
	//   one bit at a time.
	// </summary>
	public class ComposedCast : Expression, ITypeExpression {
		Expression left;
		string dim;
		
		public ComposedCast (Expression left, string dim, Location l)
		{
			this.left = left;
			this.dim = dim;
			loc = l;
		}

		public Expression DoResolveType (EmitContext ec)
		{
			Type ltype = ec.DeclSpace.ResolveType (left, false, loc);
			if (ltype == null)
				return null;

			//
			// ltype.Fullname is already fully qualified, so we can skip
			// a lot of probes, and go directly to TypeManager.LookupType
			//
			string cname = ltype.FullName + dim;
			type = TypeManager.LookupTypeDirect (cname);
			if (type == null){
				//
				// For arrays of enumerations we are having a problem
				// with the direct lookup.  Need to investigate.
				//
				// For now, fall back to the full lookup in that case.
				//
				type = RootContext.LookupType (
					ec.DeclSpace, cname, false, loc);

				if (type == null)
					return null;
			}

			if (!ec.ResolvingTypeTree){
				//
				// If the above flag is set, this is being invoked from the ResolveType function.
				// Upper layers take care of the type validity in this context.
				//
			if (!ec.InUnsafe && type.IsPointer){
				UnsafeError (loc);
				return null;
			}
			}
			
			eclass = ExprClass.Type;
			return this;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			return DoResolveType (ec);
		}

		public override void Emit (EmitContext ec)
		{
			throw new Exception ("This should never be called");
		}

		public override string ToString ()
		{
			return left + dim;
		}
	}

	//
	// This class is used to represent the address of an array, used
	// only by the Fixed statement, this is like the C "&a [0]" construct.
	//
	public class ArrayPtr : Expression {
		Expression array;
		
		public ArrayPtr (Expression array, Location l)
		{
			Type array_type = array.Type.GetElementType ();

			this.array = array;
			
			string array_ptr_type_name = array_type.FullName + "*";
			
			type = Type.GetType (array_ptr_type_name);
			if (type == null){
				ModuleBuilder mb = CodeGen.ModuleBuilder;
				
				type = mb.GetType (array_ptr_type_name);
			}

			eclass = ExprClass.Value;
			loc = l;
		}

		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;
			
			array.Emit (ec);
			IntLiteral.EmitInt (ig, 0);
			ig.Emit (OpCodes.Ldelema, array.Type.GetElementType ());
		}

		public override Expression DoResolve (EmitContext ec)
		{
			//
			// We are born fully resolved
			//
			return this;
		}
	}

	//
	// Used by the fixed statement
	//
	public class StringPtr : Expression {
		LocalBuilder b;
		
		public StringPtr (LocalBuilder b, Location l)
		{
			this.b = b;
			eclass = ExprClass.Value;
			type = TypeManager.char_ptr_type;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			// This should never be invoked, we are born in fully
			// initialized state.

			return this;
		}

		public override void Emit (EmitContext ec)
		{
			ILGenerator ig = ec.ig;

			ig.Emit (OpCodes.Ldloc, b);
			ig.Emit (OpCodes.Conv_I);
			ig.Emit (OpCodes.Call, TypeManager.int_get_offset_to_string_data);
			ig.Emit (OpCodes.Add);
		}
	}
	
	//
	// Implements the 'stackalloc' keyword
	//
	public class StackAlloc : Expression {
		Type otype;
		Expression t;
		Expression count;
		
		public StackAlloc (Expression type, Expression count, Location l)
		{
			t = type;
			this.count = count;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			count = count.Resolve (ec);
			if (count == null)
				return null;
			
			if (count.Type != TypeManager.int32_type){
				count = ConvertImplicitRequired (ec, count, TypeManager.int32_type, loc);
				if (count == null)
					return null;
			}

			if (ec.InCatch || ec.InFinally){
				Error (255,
					      "stackalloc can not be used in a catch or finally block");
				return null;
			}

			otype = ec.DeclSpace.ResolveType (t, false, loc);

			if (otype == null)
				return null;

			if (!TypeManager.VerifyUnManaged (otype, loc))
				return null;

			string ptr_name = otype.FullName + "*";
			type = Type.GetType (ptr_name);
			if (type == null){
				ModuleBuilder mb = CodeGen.ModuleBuilder;
				
				type = mb.GetType (ptr_name);
			}
			eclass = ExprClass.Value;

			return this;
		}

		public override void Emit (EmitContext ec)
		{
			int size = GetTypeSize (otype);
			ILGenerator ig = ec.ig;
				
			if (size == 0)
				ig.Emit (OpCodes.Sizeof, otype);
			else
				IntConstant.EmitInt (ig, size);
			count.Emit (ec);
			ig.Emit (OpCodes.Mul);
			ig.Emit (OpCodes.Localloc);
		}
	}
	public class Preserve : ExpressionStatement {
		ArrayList args = null;
		MethodInfo mi = null;
		Expression target = null;
		ExpressionStatement source = null;


		public Preserve (Expression RedimTarget, ExpressionStatement acExpr, Location l)
		{
			Type type = typeof(Microsoft.VisualBasic.CompilerServices.Utils);
			mi = type.GetMethod("CopyArray");

			target = RedimTarget;
			source = acExpr;

			eclass = ExprClass.Value;
			loc = l;
		}

		public override Expression DoResolve (EmitContext ec)
		{
			//
			// We are born fully resolved
			//
			type = mi.ReturnType;

			source.Resolve (ec);

			return this;
		}

		public override void Emit (EmitContext ec)
		{
			args = new ArrayList (2);

			args.Add (new Argument (target, Argument.AType.Expression));
			args.Add (new Argument (source, Argument.AType.Expression));

			Invocation.EmitArguments (ec, mi, args);

			ec.ig.Emit (OpCodes.Call, mi);
			return;
		}

		public override void EmitStatement (EmitContext ec)
		{
			Emit (ec);
		}

	}
}