Revert this patch as it breaks mscorlib and System.Web's test compilation
[mono.git] / mcs / mcs / literal.cs
old mode 100755 (executable)
new mode 100644 (file)
index 6542f35..639e536
@@ -6,66 +6,51 @@
 //
 // (C) 2001 Ximian, Inc.
 //
+//
+// Notice that during parsing we create objects of type Literal, but the
+// types are not loaded (thats why the Resolve method has to assign the
+// type at that point).
+//
+// Literals differ from the constants in that we know we encountered them
+// as a literal in the source code (and some extra rules apply there) and
+// they have to be resolved (since during parsing we have not loaded the
+// types yet) while constants are created only after types have been loaded
+// and are fully resolved when born.
+//
 
 using System;
 using System.Reflection;
 using System.Reflection.Emit;
 
-namespace CIR {
-       public abstract class Literal : Expression {
-               // <summary>
-               //   This is different from ToString in that ToString
-               //   is supposed to be there for debugging purposes,
-               //   and is not guarantee to be useful for anything else,
-               //   AsString() will provide something that can be used
-               //   for round-tripping C# code.  Maybe it can be used
-               //   for IL assembly as well.
-               // </summary>
-               public abstract string AsString ();
-
-               override public string ToString ()
-               {
-                       return AsString ();
-               }
-
-               static public string descape (char c)
-               {
-                       switch (c){
-                       case '\a':
-                               return "\\a"; 
-                       case '\b':
-                               return "\\b"; 
-                       case '\n':
-                               return "\\n"; 
-                       case '\t':
-                               return "\\t"; 
-                       case '\v':
-                               return "\\v"; 
-                       case '\r':
-                               return "\\r"; 
-                       case '\\':
-                               return "\\\\";
-                       case '\f':
-                               return "\\f"; 
-                       case '\0':
-                               return "\\0"; 
-                       case '"':
-                               return "\\\""; 
-                       case '\'':
-                               return "\\\'"; 
-                       }
-                       return c.ToString ();
-               }
+//
+// I put System.Null just so we do not have to special case it on 
+// TypeManager.CSharpName
+//
+namespace System {
+       //
+       // Represents the Null Type, just used as a placeholder for the type in NullLiteral
+       //
+       public class Null {
+       }
+}
+       
+namespace Mono.CSharp {
 
-               protected Literal ()
-               {
-                       eclass = ExprClass.Value;
-               }
+       //
+       // The NullType just exists to compare type equality, and for
+       // expressions that might have the `null type'
+       //
+       public class NullType {
        }
 
-       public class NullLiteral : Literal {
-               public NullLiteral ()
+       //
+       // The null Literal constant
+       //
+       public class NullLiteral : Constant {
+               public NullLiteral (Location loc):
+                       base (loc)
                {
+                       eclass = ExprClass.Value;
                }
                
                override public string AsString ()
@@ -73,9 +58,14 @@ namespace CIR {
                        return "null";
                }
 
-               public override Expression Resolve (TypeContainer tc)
+               public override object GetValue ()
                {
-                       type = TypeManager.object_type;
+                       return null;
+               }
+
+               public override Expression DoResolve (EmitContext ec)
+               {
+                       type = TypeManager.null_type;
                        return this;
                }
 
@@ -83,310 +73,196 @@ namespace CIR {
                {
                        ec.ig.Emit (OpCodes.Ldnull);
                }
-       }
 
-       public class BoolLiteral : Literal {
-               bool val;
-               
-               public BoolLiteral (bool val)
+               public override Constant Increment ()
                {
-                       this.val = val;
+                       throw new NotSupportedException ();
                }
 
-               override public string AsString ()
-               {
-                       return val ? "true" : "false";
+               public override bool IsDefaultValue {
+                       get {
+                               return true;
+                       }
                }
 
-               public override Expression Resolve (TypeContainer tc)
-               {
-                       type = TypeManager.bool_type;
-
-                       return this;
+               public override bool IsNegative {
+                       get {
+                               return false;
+                       }
                }
 
-               public override void Emit (EmitContext ec)
-               {
-                       if (val)
-                               ec.ig.Emit (OpCodes.Ldc_I4_1);
-                       else
-                               ec.ig.Emit (OpCodes.Ldc_I4_0);
+               public override bool IsZeroInteger {
+                       get { return true; }
                }
-       }
 
-       public class CharLiteral : Literal {
-               char c;
-               
-               public CharLiteral (char c)
+               public override string GetSignatureForError()
                {
-                       this.c = c;
+                       return "null";
                }
 
-               override public string AsString ()
+               public override void Error_ValueCannotBeConverted (Location loc, Type t, bool expl)
                {
-                       return "\"" + descape (c) + "\"";
+                       Report.Error (37, loc, "Cannot convert null to `{0}' because it is a value type",
+                               TypeManager.CSharpName (t));
                }
 
-               public override Expression Resolve (TypeContainer tc)
+               public override Constant ToType (Type type, Location loc)
                {
-                       type = TypeManager.char_type;
+                       if (!type.IsValueType && !TypeManager.IsEnumType (type))
+                               return this;
 
-                       return this;
+                       return base.ToType (type, loc);
                }
 
-               public override void Emit (EmitContext ec)
-               {
-                       IntLiteral.EmitInt (ec.ig, c);
-               }
        }
 
-       public class IntLiteral : Literal {
-               public readonly int Value;
+       //
+       // A null literal in a pointer context
+       //
+       public class NullPointer : NullLiteral {
+               public static readonly NullLiteral Null;
 
-               public IntLiteral (int l)
+               static NullPointer ()
                {
-                       Value = l;
+                       Null = new NullPointer ();
                }
 
-               override public string AsString ()
+               private NullPointer ():
+                       base (Location.Null)
                {
-                       return Value.ToString ();
-               }
-
-               public override Expression Resolve (TypeContainer tc)
-               {
-                       type = TypeManager.int32_type;
-
-                       return this;
+                       type = TypeManager.object_type;
                }
 
                public override void Emit (EmitContext ec)
                {
                        ILGenerator ig = ec.ig;
-
-                       EmitInt (ig, Value);
-               }
-
-               static public void EmitInt (ILGenerator ig, int i)
-               {
-                       switch (i){
-                       case -1:
-                               ig.Emit (OpCodes.Ldc_I4_M1);
-                               break;
-                               
-                       case 0:
-                               ig.Emit (OpCodes.Ldc_I4_0);
-                               break;
-                               
-                       case 1:
-                               ig.Emit (OpCodes.Ldc_I4_1);
-                               break;
-                               
-                       case 2:
-                               ig.Emit (OpCodes.Ldc_I4_2);
-                               break;
-                               
-                       case 3:
-                               ig.Emit (OpCodes.Ldc_I4_3);
-                               break;
-                               
-                       case 4:
-                               ig.Emit (OpCodes.Ldc_I4_4);
-                               break;
-                               
-                       case 5:
-                               ig.Emit (OpCodes.Ldc_I4_5);
-                               break;
-                               
-                       case 6:
-                               ig.Emit (OpCodes.Ldc_I4_6);
-                               break;
                                
-                       case 7:
-                               ig.Emit (OpCodes.Ldc_I4_7);
-                               break;
-                               
-                       case 8:
-                               ig.Emit (OpCodes.Ldc_I4_8);
-                               break;
-
-                       default:
-                               if (i > 0 && i < 127){
-                                       ig.Emit (OpCodes.Ldc_I4_S, (sbyte) i);
-                               } else
-                                       ig.Emit (OpCodes.Ldc_I4, i);
-                               break;
-                       }
+                       ig.Emit (OpCodes.Ldc_I4_0);
+                       ig.Emit (OpCodes.Conv_U);
                }
        }
 
-       public class UIntLiteral : Literal {
-               public readonly uint Value;
-
-               public UIntLiteral (uint l)
+       public class BoolLiteral : BoolConstant {
+               public BoolLiteral (bool val, Location loc) : base (val, loc)
                {
-                       Value = l;
                }
 
-               override public string AsString ()
+               public override Expression DoResolve (EmitContext ec)
                {
-                       return Value.ToString ();
+                       type = TypeManager.bool_type;
+                       return this;
                }
+       }
 
-               public override Expression Resolve (TypeContainer tc)
+       public class CharLiteral : CharConstant {
+               public CharLiteral (char c, Location loc) : base (c, loc)
                {
-                       type = TypeManager.uint32_type;
+               }
 
+               public override Expression DoResolve (EmitContext ec)
+               {
+                       type = TypeManager.char_type;
                        return this;
                }
+       }
 
-               public override void Emit (EmitContext ec)
+       public class IntLiteral : IntConstant {
+               public IntLiteral (int l, Location loc) : base (l, loc)
                {
-                       ILGenerator ig = ec.ig;
-
-                       IntLiteral.EmitInt (ig, unchecked ((int) Value));
                }
 
+               public override Expression DoResolve (EmitContext ec)
+               {
+                       type = TypeManager.int32_type;
+                       return this;
+               }
        }
-       
-       public class LongLiteral : Literal {
-               public readonly long Value;
 
-               public LongLiteral (long l)
+       public class UIntLiteral : UIntConstant {
+               public UIntLiteral (uint l, Location loc) : base (l, loc)
                {
-                       Value = l;
                }
 
-               override public string AsString ()
+               public override Expression DoResolve (EmitContext ec)
+               {
+                       type = TypeManager.uint32_type;
+                       return this;
+               }
+       }
+       
+       public class LongLiteral : LongConstant {
+               public LongLiteral (long l, Location loc) : base (l, loc)
                {
-                       return Value.ToString ();
                }
 
-               public override Expression Resolve (TypeContainer tc)
+               public override Expression DoResolve (EmitContext ec)
                {
                        type = TypeManager.int64_type;
 
                        return this;
                }
+       }
 
-               public override void Emit (EmitContext ec)
+       public class ULongLiteral : ULongConstant {
+               public ULongLiteral (ulong l, Location loc) : base (l, loc)
                {
-                       ILGenerator ig = ec.ig;
-
-                       EmitLong (ig, Value);
                }
 
-               static public void EmitLong (ILGenerator ig, long l)
+               public override Expression DoResolve (EmitContext ec)
                {
-                       if (l >= -1 || l < Int32.MaxValue)
-                               IntLiteral.EmitInt (ig, (int) l);
-                       else
-                               ig.Emit (OpCodes.Ldc_I8, l);
+                       type = TypeManager.uint64_type;
+                       return this;
                }
        }
-
-       public class FloatLiteral : Literal {
-               public readonly float Value;
-
-               public FloatLiteral (float f)
-               {
-                       Value = f;
-               }
-
-               override public string AsString ()
+       
+       public class FloatLiteral : FloatConstant {
+               
+               public FloatLiteral (float f, Location loc) : base (f, loc)
                {
-                       return Value.ToString ();
                }
 
-               public override Expression Resolve (TypeContainer tc)
+               public override Expression DoResolve (EmitContext ec)
                {
                        type = TypeManager.float_type;
-
                        return this;
                }
-
-               public override void Emit (EmitContext ec)
-               {
-                       ec.ig.Emit (OpCodes.Ldc_R4, Value);
-               }
        }
 
-       public class DoubleLiteral : Literal {
-               public readonly double Value;
-
-               public DoubleLiteral (double d)
-               {
-                       Value = d;
-               }
-
-               override public string AsString ()
+       public class DoubleLiteral : DoubleConstant {
+               public DoubleLiteral (double d, Location loc) : base (d, loc)
                {
-                       return Value.ToString ();
                }
 
-               public override Expression Resolve (TypeContainer tc)
+               public override Expression DoResolve (EmitContext ec)
                {
                        type = TypeManager.double_type;
 
                        return this;
                }
-
-               public override void Emit (EmitContext ec)
-               {
-                       ec.ig.Emit (OpCodes.Ldc_R8, Value);
-               }
        }
 
-       public class DecimalLiteral : Literal {
-               public readonly decimal Value;
-
-               public DecimalLiteral (decimal d)
-               {
-                       Value = d;
-               }
-
-               override public string AsString ()
+       public class DecimalLiteral : DecimalConstant {
+               public DecimalLiteral (decimal d, Location loc) : base (d, loc)
                {
-                       return Value.ToString ();
                }
 
-               public override Expression Resolve (TypeContainer tc)
+               public override Expression DoResolve (EmitContext ec)
                {
                        type = TypeManager.decimal_type;
-
                        return this;
                }
-
-               public override void Emit (EmitContext ec)
-               {
-                       throw new Exception ("Implement me");
-               }
        }
 
-       public class StringLiteral : Literal {
-               string s;
-
-               public StringLiteral (string s)
+       public class StringLiteral : StringConstant {
+               public StringLiteral (string s, Location loc) : base (s, loc)
                {
-                       this.s = s;
                }
 
-               // FIXME: Escape the string.
-               override public string AsString ()
-               {
-                       return "\"" + s + "\"";
-               }
-
-               public override Expression Resolve (TypeContainer tc)
+               public override Expression DoResolve (EmitContext ec)
                {
                        type = TypeManager.string_type;
 
                        return this;
                }
-
-               public override void Emit (EmitContext ec)
-               {
-                       ec.ig.Emit (OpCodes.Ldstr, s);
-               }
        }
 }