// Authors:
// Miguel de Icaza (miguel@ximian.com)
// Ravi Pratap (ravi@ximian.com)
+// Marek Safar (marek.safar@gmail.com)
//
// (C) 2001, 2002, 2003 Ximian, Inc.
//
// A container class for all the conversion operations
//
public class Convert {
+#if GMCS_SOURCE
+ static bool TypeParameter_to_Null (Type target_type)
+ {
+ GenericConstraints gc = TypeManager.GetTypeParameterConstraints (target_type);
+ if (gc == null)
+ return false;
+
+ if (gc.HasReferenceTypeConstraint)
+ return true;
+ if (gc.HasClassConstraint && !TypeManager.IsValueType (gc.ClassConstraint))
+ return true;
+
+ return false;
+ }
+
+ static Type TypeParam_EffectiveBaseType (GenericConstraints gc)
+ {
+ ArrayList list = new ArrayList ();
+ list.Add (gc.EffectiveBaseClass);
+ foreach (Type t in gc.InterfaceConstraints) {
+ if (!TypeManager.IsGenericParameter (t))
+ continue;
+
+ GenericConstraints new_gc = TypeManager.GetTypeParameterConstraints (t);
+ if (new_gc != null)
+ list.Add (TypeParam_EffectiveBaseType (new_gc));
+ }
+ return FindMostEncompassedType (list);
+ }
+#endif
+
//
- // This is used to prettify the code: a null argument is allowed
- // for ImplicitStandardConversion as long as it is known that
- // no anonymous method will play a role.
+ // From a one-dimensional array-type S[] to System.Collections.IList<S> and base
+ // interfaces of this interface.
//
- // FIXME: renamed from `const' to `static' to allow bootstraping from older
- // versions of the compiler that could not cope with this construct.
+ // From a one-dimensional array-type S[] to System.Collections.IList<T> and base
+ // interfaces of this interface, provided there is an implicit reference conversion
+ // from S to T.
//
- public static EmitContext ConstantEC = null;
-
+ static bool Array_To_IList (Type array, Type list)
+ {
+#if GMCS_SOURCE
+ if (!array.IsArray || (array.GetArrayRank () != 1) || !list.IsGenericType)
+ return false;
+
+ Type gt = list.GetGenericTypeDefinition ();
+ if ((gt != TypeManager.generic_ilist_type) &&
+ (gt != TypeManager.generic_icollection_type) &&
+ (gt != TypeManager.generic_ienumerable_type))
+ return false;
+
+ Type element_type = TypeManager.GetElementType (array);
+ Type arg_type = TypeManager.GetTypeArguments (list) [0];
+
+ if (element_type == arg_type)
+ return true;
+
+ if (MyEmptyExpr == null)
+ MyEmptyExpr = new EmptyExpression ();
+ MyEmptyExpr.SetType (TypeManager.GetElementType (array));
+
+ return ImplicitReferenceConversionExists (MyEmptyExpr, arg_type);
+#else
+ return false;
+#endif
+ }
+
+ static Expression ImplicitTypeParameterConversion (Expression expr,
+ Type target_type)
+ {
+#if GMCS_SOURCE
+ Type expr_type = expr.Type;
+
+ GenericConstraints gc = TypeManager.GetTypeParameterConstraints (expr_type);
+
+ if (gc == null) {
+ if (target_type == TypeManager.object_type)
+ return new BoxedCast (expr, target_type);
+
+ return null;
+ }
+
+ // We're converting from a type parameter which is known to be a reference type.
+ Type base_type = TypeParam_EffectiveBaseType (gc);
+
+ if (TypeManager.IsSubclassOf (base_type, target_type))
+ return new ClassCast (expr, target_type);
+
+ if (target_type.IsInterface) {
+ if (TypeManager.ImplementsInterface (base_type, target_type))
+ return new ClassCast (expr, target_type);
+
+ foreach (Type t in gc.InterfaceConstraints) {
+ if (TypeManager.IsSubclassOf (t, target_type))
+ return new ClassCast (expr, target_type);
+ if (TypeManager.ImplementsInterface (t, target_type))
+ return new ClassCast (expr, target_type);
+ }
+ }
+
+ foreach (Type t in gc.InterfaceConstraints) {
+ if (!TypeManager.IsGenericParameter (t))
+ continue;
+ if (TypeManager.IsSubclassOf (t, target_type))
+ return new ClassCast (expr, target_type);
+ if (TypeManager.ImplementsInterface (t, target_type))
+ return new ClassCast (expr, target_type);
+ }
+#endif
+ return null;
+ }
+
+ static bool ExplicitTypeParameterConversionExists (Type source_type, Type target_type)
+ {
+#if GMCS_SOURCE
+ if (target_type.IsInterface)
+ return true;
+
+ if (TypeManager.IsGenericParameter (target_type)) {
+ GenericConstraints gc = TypeManager.GetTypeParameterConstraints (target_type);
+ if (gc == null)
+ return false;
+
+ foreach (Type iface in gc.InterfaceConstraints) {
+ if (!TypeManager.IsGenericParameter (iface))
+ continue;
+
+ if (TypeManager.IsSubclassOf (source_type, iface))
+ return true;
+ }
+ }
+#endif
+ return false;
+ }
+
+ static Expression ExplicitTypeParameterConversion (Expression source, Type target_type)
+ {
+#if GMCS_SOURCE
+ Type source_type = source.Type;
+
+ if (target_type.IsInterface)
+ return new ClassCast (source, target_type);
+
+ if (TypeManager.IsGenericParameter (target_type)) {
+ GenericConstraints gc = TypeManager.GetTypeParameterConstraints (target_type);
+ if (gc == null)
+ return null;
+
+ foreach (Type iface in gc.InterfaceConstraints) {
+ if (!TypeManager.IsGenericParameter (iface))
+ continue;
+
+ if (TypeManager.IsSubclassOf (source_type, iface))
+ return new ClassCast (source, target_type);
+ }
+ }
+#endif
+ return null;
+ }
+
static EmptyExpression MyEmptyExpr;
static public Expression ImplicitReferenceConversion (Expression expr, Type target_type)
{
if (expr_type == TypeManager.void_type)
return null;
-
+
+ if (TypeManager.IsGenericParameter (expr_type))
+ return ImplicitTypeParameterConversion (expr, target_type);
+
//
// notice that it is possible to write "ValueType v = 1", the ValueType here
// is an abstract class, and not really a value type, so we apply the same rules.
if (target_type == TypeManager.object_type) {
//
// A pointer type cannot be converted to object
- //
+ //
if (expr_type.IsPointer)
return null;
- if (expr_type.IsValueType)
+ if (TypeManager.IsValueType (expr_type))
return new BoxedCast (expr, target_type);
if (expr_type.IsClass || expr_type.IsInterface || expr_type == TypeManager.enum_type){
if (expr_type == TypeManager.anonymous_method_type)
return null;
} else if (target_type == TypeManager.value_type) {
- if (expr_type.IsValueType)
+ if (TypeManager.IsValueType (expr_type))
return new BoxedCast (expr, target_type);
if (expr_type == TypeManager.null_type)
- return new NullCast ((Constant)expr, target_type);
+ return new EmptyConstantCast ((Constant)expr, target_type);
return null;
- } else if (expr_type.IsSubclassOf (target_type)) {
+ } else if (TypeManager.IsSubclassOf (expr_type, target_type)) {
//
// Special case: enumeration to System.Enum.
// System.Enum is not a value type, it is a class, so we need
// a boxing conversion
//
- if (expr_type.IsEnum)
+ if (expr_type.IsEnum || TypeManager.IsGenericParameter (expr_type))
return new BoxedCast (expr, target_type);
return new EmptyCast (expr, target_type);
// Always ensure that the code here and there is in sync
// from the null type to any reference-type.
- if (expr_type == TypeManager.null_type){
- if (target_type.IsPointer)
- return new EmptyCast (NullPointer.Null, target_type);
-
- if (!target_type.IsValueType) {
- if (expr is Constant)
- return new NullCast ((Constant)expr, target_type);
-
- // I found only one case when it happens -- Foo () ? null : null;
- Report.Warning (-100, 1, expr.Location, "The result of the expression is always `null'");
- return new NullCast (new NullLiteral (expr.Location), target_type);
- }
+ if (expr_type == TypeManager.null_type) {
+ NullConstant nc = (NullConstant)expr;
+ return nc.ConvertImplicitly(target_type);
}
// from any class-type S to any interface-type T.
}
if (TypeManager.ImplementsInterface (expr_type, target_type)){
- if (expr_type.IsClass)
- return new EmptyCast (expr, target_type);
- else if (expr_type.IsValueType)
+ if (TypeManager.IsGenericParameter (expr_type) || TypeManager.IsValueType (expr_type))
return new BoxedCast (expr, target_type);
else
return new EmptyCast (expr, target_type);
else
return null;
}
-
+
// from an array-type S to an array-type of type T
if (expr_type.IsArray && target_type.IsArray) {
if (expr_type.GetArrayRank () == target_type.GetArrayRank ()) {
if (MyEmptyExpr == null)
MyEmptyExpr = new EmptyExpression ();
-
+
MyEmptyExpr.SetType (expr_element_type);
Type target_element_type = TypeManager.GetElementType (target_type);
if (!expr_element_type.IsValueType && !target_element_type.IsValueType)
- if (ImplicitStandardConversionExists (ConstantEC, MyEmptyExpr,
+ if (ImplicitStandardConversionExists (MyEmptyExpr,
target_element_type))
return new EmptyCast (expr, target_type);
}
}
-
+
// from an array-type to System.Array
if (expr_type.IsArray && target_type == TypeManager.array_type)
return new EmptyCast (expr, target_type);
-
+
+ // from an array-type of type T to IList<T>
+ if (expr_type.IsArray && Array_To_IList (expr_type, target_type))
+ return new EmptyCast (expr, target_type);
+
// from any delegate type to System.Delegate
- if ((expr_type == TypeManager.delegate_type ||
- expr_type.IsSubclassOf (TypeManager.delegate_type)) &&
+ if ((expr_type == TypeManager.delegate_type || TypeManager.IsDelegateType (expr_type)) &&
target_type == TypeManager.delegate_type)
return new EmptyCast (expr, target_type);
-
+
// from any array-type or delegate type into System.ICloneable.
if (expr_type.IsArray ||
- expr_type == TypeManager.delegate_type ||
- expr_type.IsSubclassOf (TypeManager.delegate_type))
+ expr_type == TypeManager.delegate_type || TypeManager.IsDelegateType (expr_type))
if (target_type == TypeManager.icloneable_type)
return new EmptyCast (expr, target_type);
-
+
+ // from a generic type definition to a generic instance.
+ if (TypeManager.IsEqual (expr_type, target_type))
+ return new EmptyCast (expr, target_type);
+
return null;
}
// Tests whether an implicit reference conversion exists between expr_type
// and target_type
//
- static bool ImplicitReferenceConversionExists (Expression expr, Type target_type)
+ public static bool ImplicitReferenceConversionExists (Expression expr, Type target_type)
{
if (target_type.IsValueType)
return false;
Type expr_type = expr.Type;
+ if (TypeManager.IsGenericParameter (expr_type))
+ return ImplicitTypeParameterConversion (expr, target_type) != null;
+
//
// This is the boxed case.
//
if (target_type == TypeManager.object_type) {
- if (expr_type.IsClass || expr_type.IsValueType ||
+ if (expr_type.IsClass || TypeManager.IsValueType (expr_type) ||
expr_type.IsInterface || expr_type == TypeManager.enum_type)
if (target_type != TypeManager.anonymous_method_type)
- return true;
+ return true;
return false;
- } else if (expr_type.IsSubclassOf (target_type))
+ } else if (TypeManager.IsSubclassOf (expr_type, target_type))
return true;
// Please remember that all code below actually comes
// from ImplicitReferenceConversion so make sure code remains in sync
-
+
// from any class-type S to any interface-type T.
if (target_type.IsInterface) {
if (target_type != TypeManager.iconvertible_type &&
expr is UIntLiteral || expr is ULongLiteral)) {
return false;
}
-
+
if (TypeManager.ImplementsInterface (expr_type, target_type))
return true;
}
-
+
// from any interface type S to interface-type T.
if (expr_type.IsInterface && target_type.IsInterface)
if (TypeManager.ImplementsInterface (expr_type, target_type))
return true;
-
+
// from an array-type S to an array-type of type T
if (expr_type.IsArray && target_type.IsArray) {
if (expr_type.GetArrayRank () == target_type.GetArrayRank ()) {
-
+
Type expr_element_type = expr_type.GetElementType ();
if (MyEmptyExpr == null)
MyEmptyExpr = new EmptyExpression ();
-
+
MyEmptyExpr.SetType (expr_element_type);
Type target_element_type = TypeManager.GetElementType (target_type);
-
+
if (!expr_element_type.IsValueType && !target_element_type.IsValueType)
- if (ImplicitStandardConversionExists (ConstantEC, MyEmptyExpr,
+ if (ImplicitStandardConversionExists (MyEmptyExpr,
target_element_type))
return true;
}
}
-
+
// from an array-type to System.Array
if (expr_type.IsArray && (target_type == TypeManager.array_type))
return true;
-
+
+ // from an array-type of type T to IList<T>
+ if (expr_type.IsArray && Array_To_IList (expr_type, target_type))
+ return true;
+
// from any delegate type to System.Delegate
- if ((expr_type == TypeManager.delegate_type ||
- expr_type.IsSubclassOf (TypeManager.delegate_type)) &&
+ if ((expr_type == TypeManager.delegate_type || TypeManager.IsDelegateType (expr_type)) &&
target_type == TypeManager.delegate_type)
if (target_type.IsAssignableFrom (expr_type))
return true;
-
+
// from any array-type or delegate type into System.ICloneable.
if (expr_type.IsArray ||
- expr_type == TypeManager.delegate_type ||
- expr_type.IsSubclassOf (TypeManager.delegate_type))
+ expr_type == TypeManager.delegate_type || TypeManager.IsDelegateType (expr_type))
if (target_type == TypeManager.icloneable_type)
return true;
-
+
// from the null type to any reference-type.
if (expr_type == TypeManager.null_type){
if (target_type.IsPointer)
return true;
-
+
if (!target_type.IsValueType)
return true;
}
+
+ // from a generic type definition to a generic instance.
+ if (TypeManager.IsEqual (expr_type, target_type))
+ return true;
+
return false;
}
/// expr is the expression to convert, returns a new expression of type
/// target_type or null if an implicit conversion is not possible.
/// </summary>
- static public Expression ImplicitNumericConversion (EmitContext ec, Expression expr,
+ static public Expression ImplicitNumericConversion (Expression expr,
Type target_type)
{
Type expr_type = expr.Type;
-
- //
- // Attempt to do the implicit constant expression conversions
-
- if (expr is Constant){
- if (expr is IntConstant){
- Expression e;
-
- e = TryImplicitIntConversion (target_type, (IntConstant) expr);
-
- if (e != null)
- return e;
- } else if (expr is LongConstant && target_type == TypeManager.uint64_type){
- //
- // Try the implicit constant expression conversion
- // from long to ulong, instead of a nice routine,
- // we just inline it
- //
- long v = ((LongConstant) expr).Value;
- if (v >= 0)
- return new ULongConstant ((ulong) v, expr.Location);
- }
- }
-
- Type real_target_type = target_type;
+ Type real_target_type = target_type;
if (expr_type == TypeManager.sbyte_type){
//
} else if (expr_type == TypeManager.byte_type){
//
// From byte to short, ushort, int, uint, long, ulong, float, double, decimal
- //
+ //
if ((real_target_type == TypeManager.short_type) ||
(real_target_type == TypeManager.ushort_type) ||
(real_target_type == TypeManager.int32_type) ||
return new OpcodeCast (expr, target_type, OpCodes.Conv_R8);
if (real_target_type == TypeManager.decimal_type)
return new CastToDecimal (expr);
-
+
} else if (expr_type == TypeManager.short_type){
//
// From short to int, long, float, double, decimal
- //
+ //
if (real_target_type == TypeManager.int32_type)
return new EmptyCast (expr, target_type);
if (real_target_type == TypeManager.int64_type)
return new OpcodeCast (expr, target_type, OpCodes.Conv_R4);
if (real_target_type == TypeManager.decimal_type)
return new CastToDecimal (expr);
-
+
} else if (expr_type == TypeManager.ushort_type){
//
// From ushort to int, uint, long, ulong, float, double, decimal
} else if (expr_type == TypeManager.char_type){
//
// From char to ushort, int, uint, long, ulong, float, double, decimal
- //
+ //
if ((real_target_type == TypeManager.ushort_type) ||
(real_target_type == TypeManager.int32_type) ||
(real_target_type == TypeManager.uint32_type))
/// </summary>
public static bool ImplicitConversionExists (EmitContext ec, Expression expr, Type target_type)
{
- if (ImplicitStandardConversionExists (ec, expr, target_type))
- return true;
-
- Expression dummy = ImplicitUserConversion (ec, expr, target_type, Location.Null);
+#if GMCS_SOURCE
+ if (expr is NullLiteral) {
+ if (TypeManager.IsGenericParameter (target_type))
+ return TypeParameter_to_Null (target_type);
- if (dummy != null)
+ if (TypeManager.IsNullableType (target_type))
+ return true;
+ }
+#endif
+ if (ImplicitStandardConversionExists (expr, target_type))
return true;
- return false;
+ return ImplicitUserConversion (ec, expr, target_type, Location.Null) != null;
}
public static bool ImplicitUserConversionExists (EmitContext ec, Type source, Type target)
///
/// ec should point to a real EmitContext if expr.Type is TypeManager.anonymous_method_type.
/// </summary>
- public static bool ImplicitStandardConversionExists (EmitContext ec, Expression expr, Type target_type)
+ public static bool ImplicitStandardConversionExists (Expression expr, Type target_type)
{
Type expr_type = expr.Type;
-
+#if GMCS_SOURCE
+ if (TypeManager.IsNullableType (target_type)) {
+ // if implicit standard conversion S -> T exists, S -> T? and S? -> T? also exists
+ target_type = TypeManager.GetTypeArguments (target_type) [0];
+
+ // S? -> T?
+ if (TypeManager.IsNullableType (expr_type)) {
+ EmptyExpression new_expr = EmptyExpression.Grab ();
+ new_expr.SetType (TypeManager.GetTypeArguments (expr_type) [0]);
+ bool retval = ImplicitStandardConversionExists (new_expr, target_type);
+ EmptyExpression.Release (new_expr);
+ return retval;
+ }
+ }
+#endif
if (expr_type == TypeManager.void_type)
return false;
- if (expr_type == target_type)
+ //Console.WriteLine ("Expr is {0}", expr);
+ //Console.WriteLine ("{0} -> {1} ?", expr_type, target_type);
+ if (TypeManager.IsEqual (expr_type, target_type))
return true;
- // First numeric conversions
+ // First numeric conversions
if (expr_type == TypeManager.sbyte_type){
//
// From sbyte to short, int, long, float, double, decimal
//
- if ((target_type == TypeManager.int32_type) ||
+ if ((target_type == TypeManager.int32_type) ||
(target_type == TypeManager.int64_type) ||
(target_type == TypeManager.double_type) ||
(target_type == TypeManager.float_type) ||
(target_type == TypeManager.short_type) ||
(target_type == TypeManager.decimal_type))
return true;
-
+
} else if (expr_type == TypeManager.byte_type){
//
// From byte to short, ushort, int, uint, long, ulong, float, double, decimal
- //
+ //
if ((target_type == TypeManager.short_type) ||
(target_type == TypeManager.ushort_type) ||
(target_type == TypeManager.int32_type) ||
(target_type == TypeManager.double_type) ||
(target_type == TypeManager.decimal_type))
return true;
-
+
} else if (expr_type == TypeManager.short_type){
//
- // From short to int, long, double, float, decimal
- //
+ // From short to int, long, double, float, decimal
+ //
if ((target_type == TypeManager.int32_type) ||
(target_type == TypeManager.int64_type) ||
(target_type == TypeManager.double_type) ||
(target_type == TypeManager.float_type) ||
(target_type == TypeManager.decimal_type))
return true;
-
+
} else if (expr_type == TypeManager.ushort_type){
//
// From ushort to int, uint, long, ulong, double, float, decimal
(target_type == TypeManager.float_type) ||
(target_type == TypeManager.decimal_type))
return true;
-
+
} else if (expr_type == TypeManager.int32_type){
//
// From int to long, double, float, decimal
(target_type == TypeManager.float_type) ||
(target_type == TypeManager.decimal_type))
return true;
-
+
} else if (expr_type == TypeManager.uint32_type){
//
// From uint to long, ulong, double, float, decimal
(target_type == TypeManager.float_type) ||
(target_type == TypeManager.decimal_type))
return true;
-
+
} else if ((expr_type == TypeManager.uint64_type) ||
(expr_type == TypeManager.int64_type)) {
//
(target_type == TypeManager.float_type) ||
(target_type == TypeManager.decimal_type))
return true;
-
+
} else if (expr_type == TypeManager.char_type){
//
// From char to ushort, int, uint, ulong, long, float, double, decimal
- //
+ //
if ((target_type == TypeManager.ushort_type) ||
(target_type == TypeManager.int32_type) ||
(target_type == TypeManager.uint32_type) ||
//
if (target_type == TypeManager.double_type)
return true;
- }
-
+ }
+
if (expr.eclass == ExprClass.MethodGroup){
if (TypeManager.IsDelegateType (target_type) && RootContext.Version != LanguageVersion.ISO_1){
MethodGroupExpr mg = expr as MethodGroupExpr;
if (mg != null){
- //
- // This should not happen frequently, so we can create an object
- // to test compatibility
- //
- Expression c = ImplicitDelegateCreation.Create (
- ec, mg, target_type, true, Location.Null);
- return c != null;
+ return DelegateCreation.ImplicitStandardConversionExists (mg, target_type) != null;
}
}
}
-
+
if (ImplicitReferenceConversionExists (expr, target_type))
return true;
if (value >= 0)
return true;
}
-
+
if (value == 0 && expr is IntLiteral && TypeManager.IsEnumType (target_type))
return true;
}
if (v >= 0)
return true;
}
-
+
if ((target_type == TypeManager.enum_type ||
target_type.IsSubclassOf (TypeManager.enum_type)) &&
expr is IntLiteral){
//
// If `expr_type' implements `target_type' (which is an iface)
// see TryImplicitIntConversion
- //
+ //
if (target_type.IsInterface && target_type.IsAssignableFrom (expr_type))
return true;
if (!TypeManager.IsDelegateType (target_type))
return false;
- AnonymousMethod am = (AnonymousMethod) expr;
-
- Expression conv = am.Compatible (ec, target_type, true);
- if (conv != null)
- return true;
+ AnonymousMethodExpression ame = (AnonymousMethodExpression) expr;
+ return ame.ImplicitStandardConversionExists (target_type);
}
return false;
/// Finds "most encompassed type" according to the spec (13.4.2)
/// amongst the methods in the MethodGroupExpr
/// </summary>
- static Type FindMostEncompassedType (EmitContext ec, ArrayList types)
+ static Type FindMostEncompassedType (ArrayList types)
{
Type best = null;
}
expr.SetType (t);
- if (ImplicitStandardConversionExists (ec, expr, best))
+ if (ImplicitStandardConversionExists (expr, best))
best = t;
}
foreach (Type t in types) {
if (best == t)
continue;
- if (!ImplicitStandardConversionExists (ec, expr, t)) {
+ if (!ImplicitStandardConversionExists (expr, t)) {
best = null;
break;
}
return best;
}
-
+
/// <summary>
/// Finds "most encompassing type" according to the spec (13.4.2)
/// amongst the types in the given set
/// </summary>
- static Type FindMostEncompassingType (EmitContext ec, ArrayList types)
+ static Type FindMostEncompassingType (ArrayList types)
{
Type best = null;
}
expr.SetType (best);
- if (ImplicitStandardConversionExists (ec, expr, t))
+ if (ImplicitStandardConversionExists (expr, t))
best = t;
}
if (best == t)
continue;
expr.SetType (t);
- if (!ImplicitStandardConversionExists (ec, expr, best)) {
+ if (!ImplicitStandardConversionExists (expr, best)) {
best = null;
break;
}
/// by making use of FindMostEncomp* methods. Applies the correct rules separately
/// for explicit and implicit conversion operators.
/// </summary>
- static public Type FindMostSpecificSource (EmitContext ec, IList list,
+ static public Type FindMostSpecificSource (IList list,
Expression source, bool apply_explicit_conv_rules)
{
ArrayList src_types_set = new ArrayList ();
-
+
//
// If any operator converts from S then Sx = S
//
src_types_set.Add (param_type);
}
-
+
//
// Explicit Conv rules
//
ArrayList candidate_set = new ArrayList ();
foreach (Type param_type in src_types_set){
- if (ImplicitStandardConversionExists (ec, source, param_type))
+ if (ImplicitStandardConversionExists (source, param_type))
candidate_set.Add (param_type);
}
if (candidate_set.Count != 0)
- return FindMostEncompassedType (ec, candidate_set);
+ return FindMostEncompassedType (candidate_set);
}
//
// Final case
//
if (apply_explicit_conv_rules)
- return FindMostEncompassingType (ec, src_types_set);
+ return FindMostEncompassingType (src_types_set);
else
- return FindMostEncompassedType (ec, src_types_set);
+ return FindMostEncompassedType (src_types_set);
}
-
+
/// <summary>
/// Finds the most specific target Tx according to section 13.4.4
/// </summary>
- static public Type FindMostSpecificTarget (EmitContext ec, IList list,
+ static public Type FindMostSpecificTarget (IList list,
Type target, bool apply_explicit_conv_rules)
{
ArrayList tgt_types_set = new ArrayList ();
-
+
//
// If any operator converts to T then Tx = T
//
foreach (Type ret_type in tgt_types_set){
expr.SetType (ret_type);
-
- if (ImplicitStandardConversionExists (ec, expr, target))
+
+ if (ImplicitStandardConversionExists (expr, target))
candidate_set.Add (ret_type);
}
EmptyExpression.Release (expr);
if (candidate_set.Count != 0)
- return FindMostEncompassingType (ec, candidate_set);
+ return FindMostEncompassingType (candidate_set);
}
-
+
//
// Okay, final case !
//
if (apply_explicit_conv_rules)
- return FindMostEncompassedType (ec, tgt_types_set);
- else
- return FindMostEncompassingType (ec, tgt_types_set);
+ return FindMostEncompassedType (tgt_types_set);
+ else
+ return FindMostEncompassingType (tgt_types_set);
}
-
+
/// <summary>
/// User-defined Implicit conversions
/// </summary>
return UserDefinedConversion (ec, source, target, loc, true);
}
- static void AddConversionOperators (EmitContext ec, ArrayList list,
- Expression source, Type target_type,
+ static void AddConversionOperators (ArrayList list,
+ Expression source, Type target_type,
bool look_for_explicit,
MethodGroupExpr mg)
{
Type arg_type = pd.ParameterType (0);
if (source_type != arg_type) {
- if (!ImplicitStandardConversionExists (ec, source, arg_type)) {
+ if (!ImplicitStandardConversionExists (source, arg_type)) {
if (!look_for_explicit)
continue;
expr.SetType (arg_type);
- if (!ImplicitStandardConversionExists (ec, expr, source_type))
+ if (!ImplicitStandardConversionExists (expr, source_type))
continue;
}
}
if (target_type != return_type) {
expr.SetType (return_type);
- if (!ImplicitStandardConversionExists (ec, expr, target_type)) {
+ if (!ImplicitStandardConversionExists (expr, target_type)) {
if (!look_for_explicit)
continue;
expr.SetType (target_type);
- if (!ImplicitStandardConversionExists (ec, expr, return_type))
+ if (!ImplicitStandardConversionExists (expr, return_type))
continue;
}
}
}
/// <summary>
- /// Compute the user-defined conversion operator from source_type to target_type.
+ /// Compute the user-defined conversion operator from source_type to target_type.
/// `look_for_explicit' controls whether we should also include the list of explicit operators
/// </summary>
- static MethodInfo GetConversionOperator (EmitContext ec, Expression source, Type target_type, bool look_for_explicit)
+ static MethodInfo GetConversionOperator (Type container_type, Expression source, Type target_type, bool look_for_explicit)
{
ArrayList ops = new ArrayList (4);
Type source_type = source.Type;
if (source_type != TypeManager.decimal_type) {
- AddConversionOperators (ec, ops, source, target_type, look_for_explicit,
- Expression.MethodLookup (ec, source_type, "op_Implicit", Location.Null) as MethodGroupExpr);
+ AddConversionOperators (ops, source, target_type, look_for_explicit,
+ Expression.MethodLookup (container_type, source_type, "op_Implicit", Location.Null) as MethodGroupExpr);
if (look_for_explicit) {
- AddConversionOperators (ec, ops, source, target_type, look_for_explicit,
+ AddConversionOperators (ops, source, target_type, look_for_explicit,
Expression.MethodLookup (
- ec, source_type, "op_Explicit", Location.Null) as MethodGroupExpr);
+ container_type, source_type, "op_Explicit", Location.Null) as MethodGroupExpr);
}
}
if (target_type != TypeManager.decimal_type) {
- AddConversionOperators (ec, ops, source, target_type, look_for_explicit,
- Expression.MethodLookup (ec, target_type, "op_Implicit", Location.Null) as MethodGroupExpr);
+ AddConversionOperators (ops, source, target_type, look_for_explicit,
+ Expression.MethodLookup (container_type, target_type, "op_Implicit", Location.Null) as MethodGroupExpr);
if (look_for_explicit) {
- AddConversionOperators (ec, ops, source, target_type, look_for_explicit,
+ AddConversionOperators (ops, source, target_type, look_for_explicit,
Expression.MethodLookup (
- ec, target_type, "op_Explicit", Location.Null) as MethodGroupExpr);
+ container_type, target_type, "op_Explicit", Location.Null) as MethodGroupExpr);
}
}
if (ops.Count == 0)
return null;
- Type most_specific_source = FindMostSpecificSource (ec, ops, source, look_for_explicit);
+ Type most_specific_source = FindMostSpecificSource (ops, source, look_for_explicit);
if (most_specific_source == null)
return null;
- Type most_specific_target = FindMostSpecificTarget (ec, ops, target_type, look_for_explicit);
+ Type most_specific_target = FindMostSpecificTarget (ops, target_type, look_for_explicit);
if (most_specific_target == null)
return null;
if (!(source is Constant) && hash.Lookup (source_type, target, out o)) {
method = (MethodInfo) o;
} else {
- method = GetConversionOperator (ec, source, target, look_for_explicit);
+ method = GetConversionOperator (null, source, target, look_for_explicit);
if (!(source is Constant))
hash.Insert (source_type, target, method);
}
if (method == null)
return null;
-
+
Type most_specific_source = TypeManager.GetParameterData (method).ParameterType (0);
//
return e;
}
-
+
/// <summary>
/// Converts implicitly the resolved expression `expr' into the
/// `target_type'. It returns a new expression that can be used
- /// in a context that expects a `target_type'.
+ /// in a context that expects a `target_type'.
/// </summary>
static public Expression ImplicitConversion (EmitContext ec, Expression expr,
Type target_type, Location loc)
return null;
}
-
+
/// <summary>
/// Attempts to apply the `Standard Implicit
/// Conversion' rules to the expression `expr' into
/// `target_type'.
///
/// This is different from `ImplicitConversion' in that the
- /// user defined implicit conversions are excluded.
+ /// user defined implicit conversions are excluded.
/// </summary>
static public Expression ImplicitConversionStandard (EmitContext ec, Expression expr,
Type target_type, Location loc)
{
Type expr_type = expr.Type;
Expression e;
+#if GMCS_SOURCE
+ // TODO: refactor to be a part of constant infrastructure
+ if (expr is NullLiteral) {
+ if (TypeManager.IsNullableType (target_type))
+ return new Nullable.NullableLiteral (target_type, loc);
+ }
+
+ if (TypeManager.IsNullableType (target_type)) {
+ Type target = TypeManager.GetTypeArguments (target_type) [0];
+ if (TypeManager.IsNullableType (expr.Type)) {
+ e = new Nullable.LiftedConversion (
+ expr, target_type, false, false, loc).Resolve (ec);
+ if (e != null)
+ return e;
+ } else {
+ e = ImplicitConversion (ec, expr, target, loc);
+ if (e != null)
+ return Nullable.Wrap.Create (e, ec);
+ }
+ }
+#endif
if (expr.eclass == ExprClass.MethodGroup){
if (!TypeManager.IsDelegateType (target_type)){
return null;
}
-
+
//
// Only allow anonymous method conversions on post ISO_1
//
MethodGroupExpr mg = expr as MethodGroupExpr;
if (mg != null)
return ImplicitDelegateCreation.Create (
- ec, mg, target_type, false, loc);
+ ec, mg, target_type, loc);
}
}
- if (expr_type == target_type && expr_type != TypeManager.null_type)
+ if (expr_type.Equals (target_type) && !TypeManager.IsNullType (expr_type))
return expr;
- e = ImplicitNumericConversion (ec, expr, target_type);
+ //
+ // Attempt to do the implicit constant expression conversions
+ //
+ Constant c = expr as Constant;
+ if (c != null) {
+ //
+ // If `target_type' is an interface and the type of `ic' implements the interface
+ // e.g. target_type is IComparable, IConvertible, IFormattable
+ //
+ if (c.Type == TypeManager.int32_type && target_type.IsInterface && target_type.IsAssignableFrom (c.Type))
+ return new BoxedCast (c, target_type);
+
+ try {
+ c = c.ConvertImplicitly (target_type);
+ } catch {
+ Console.WriteLine ("Conversion error happened in line {0}", loc);
+ throw;
+ }
+ if (c != null)
+ return c;
+ }
+
+ e = ImplicitNumericConversion (expr, target_type);
if (e != null)
return e;
e = ImplicitReferenceConversion (expr, target_type);
if (e != null)
return e;
-
- if ((target_type == TypeManager.enum_type ||
- target_type.IsSubclassOf (TypeManager.enum_type)) &&
- expr is IntLiteral){
+
+ if (TypeManager.IsEnumType (target_type) && expr is IntLiteral){
IntLiteral i = (IntLiteral) expr;
-
+
if (i.Value == 0)
return new EnumConstant ((Constant) expr, target_type);
}
//return null;
}
}
-
+
if (expr_type == TypeManager.null_type && target_type.IsPointer)
return new EmptyCast (NullPointer.Null, target_type);
}
if (expr_type == TypeManager.anonymous_method_type){
- if (!TypeManager.IsDelegateType (target_type)){
- Report.Error (1660, loc,
- "Cannot convert anonymous method block to type `{0}' because it is not a delegate type",
- TypeManager.CSharpName (target_type));
- return null;
- }
+ AnonymousMethodExpression ame = (AnonymousMethodExpression) expr;
- AnonymousMethod am = (AnonymousMethod) expr;
int errors = Report.Errors;
- Expression conv = am.Compatible (ec, target_type, false);
+ Expression conv = ame.Compatible (ec, target_type);
if (conv != null)
return conv;
if (errors != Report.Errors)
return new EmptyCast (expr, target_type);
}
-
- return null;
- }
-
- /// <summary>
- /// Attempts to perform an implicit constant conversion of the IntConstant
- /// into a different data type using casts (See Implicit Constant
- /// Expression Conversions)
- /// </summary>
- static public Expression TryImplicitIntConversion (Type target_type, IntConstant ic)
- {
- int value = ic.Value;
-
- if (target_type == TypeManager.sbyte_type){
- if (value >= SByte.MinValue && value <= SByte.MaxValue)
- return new SByteConstant ((sbyte) value, ic.Location);
- } else if (target_type == TypeManager.byte_type){
- if (value >= Byte.MinValue && value <= Byte.MaxValue)
- return new ByteConstant ((byte) value, ic.Location);
- } else if (target_type == TypeManager.short_type){
- if (value >= Int16.MinValue && value <= Int16.MaxValue)
- return new ShortConstant ((short) value, ic.Location);
- } else if (target_type == TypeManager.ushort_type){
- if (value >= UInt16.MinValue && value <= UInt16.MaxValue)
- return new UShortConstant ((ushort) value, ic.Location);
- } else if (target_type == TypeManager.uint32_type){
- if (value >= 0)
- return new UIntConstant ((uint) value, ic.Location);
- } else if (target_type == TypeManager.uint64_type){
- //
- // we can optimize this case: a positive int32
- // always fits on a uint64. But we need an opcode
- // to do it.
- //
- if (value >= 0)
- return new ULongConstant ((ulong) value, ic.Location);
- } else if (target_type == TypeManager.double_type)
- return new DoubleConstant ((double) value, ic.Location);
- else if (target_type == TypeManager.float_type)
- return new FloatConstant ((float) value, ic.Location);
-
- if (value == 0 && ic is IntLiteral && TypeManager.IsEnumType (target_type)){
- Type underlying = TypeManager.EnumToUnderlying (target_type);
- Constant e = (Constant) ic;
-
- //
- // Possibly, we need to create a different 0 literal before passing
- // to EnumConstant
- //
- if (underlying == TypeManager.int64_type)
- e = new LongLiteral (0, ic.Location);
- else if (underlying == TypeManager.uint64_type)
- e = new ULongLiteral (0, ic.Location);
-
- return new EnumConstant (e, target_type);
- }
-
- //
- // If `target_type' is an interface and the type of `ic' implements the interface
- // e.g. target_type is IComparable, IConvertible, IFormattable
- //
- if (target_type.IsInterface && target_type.IsAssignableFrom (ic.Type))
- return new BoxedCast (ic, target_type);
return null;
}
static public Expression ImplicitConversionRequired (EmitContext ec, Expression source,
Type target_type, Location loc)
{
- Expression e;
-
- e = ImplicitConversion (ec, source, target_type, loc);
+ Expression e = ImplicitConversion (ec, source, target_type, loc);
if (e != null)
return e;
- if (source is DoubleLiteral) {
- if (target_type == TypeManager.float_type) {
- Error_664 (loc, "float", "f");
- return null;
- }
- if (target_type == TypeManager.decimal_type) {
- Error_664 (loc, "decimal", "m");
- return null;
- }
- }
-
- source.Error_ValueCannotBeConverted (loc, target_type, false);
+ source.Error_ValueCannotBeConverted (ec, loc, target_type, false);
return null;
}
- static void Error_664 (Location loc, string type, string suffix) {
- Report.Error (664, loc,
- "Literal of type double cannot be implicitly converted to type `{0}'. Add suffix `{1}' to create a literal of this type",
- type, suffix);
- }
-
/// <summary>
/// Performs the explicit numeric conversions
+ ///
+ /// There are a few conversions that are not part of the C# standard,
+ /// they were interim hacks in the C# compiler that were supposed to
+ /// become explicit operators in the UIntPtr class and IntPtr class,
+ /// but for historical reasons it did not happen, so the C# compiler
+ /// ended up with these special hacks.
+ ///
+ /// See bug 59800 for details.
+ ///
+ /// The conversion are:
+ /// UIntPtr->SByte
+ /// UIntPtr->Int16
+ /// UIntPtr->Int32
+ /// IntPtr->UInt64
+ /// UInt64->IntPtr
+ /// SByte->UIntPtr
+ /// Int16->UIntPtr
+ ///
/// </summary>
public static Expression ExplicitNumericConversion (Expression expr, Type target_type)
{
if (expr_type == TypeManager.sbyte_type){
//
- // From sbyte to byte, ushort, uint, ulong, char
+ // From sbyte to byte, ushort, uint, ulong, char, uintptr
//
if (real_target_type == TypeManager.byte_type)
return new ConvCast (expr, target_type, ConvCast.Mode.I1_U1);
return new ConvCast (expr, target_type, ConvCast.Mode.I1_U8);
if (real_target_type == TypeManager.char_type)
return new ConvCast (expr, target_type, ConvCast.Mode.I1_CH);
+
+ // One of the built-in conversions that belonged in the class library
+ if (real_target_type == TypeManager.uintptr_type){
+ Expression u8e = new ConvCast (expr, TypeManager.uint64_type, ConvCast.Mode.I1_U8);
+
+ return new OperatorCast (u8e, TypeManager.uintptr_type, true);
+ }
} else if (expr_type == TypeManager.byte_type){
//
// From byte to sbyte and char
return new ConvCast (expr, target_type, ConvCast.Mode.U1_CH);
} else if (expr_type == TypeManager.short_type){
//
- // From short to sbyte, byte, ushort, uint, ulong, char
+ // From short to sbyte, byte, ushort, uint, ulong, char, uintptr
//
if (real_target_type == TypeManager.sbyte_type)
return new ConvCast (expr, target_type, ConvCast.Mode.I2_I1);
return new ConvCast (expr, target_type, ConvCast.Mode.I2_U8);
if (real_target_type == TypeManager.char_type)
return new ConvCast (expr, target_type, ConvCast.Mode.I2_CH);
+
+ // One of the built-in conversions that belonged in the class library
+ if (real_target_type == TypeManager.uintptr_type){
+ Expression u8e = new ConvCast (expr, TypeManager.uint64_type, ConvCast.Mode.I2_U8);
+
+ return new OperatorCast (u8e, TypeManager.uintptr_type, true);
+ }
} else if (expr_type == TypeManager.ushort_type){
//
// From ushort to sbyte, byte, short, char
return new ConvCast (expr, target_type, ConvCast.Mode.U2_CH);
} else if (expr_type == TypeManager.int32_type){
//
- // From int to sbyte, byte, short, ushort, uint, ulong, char
+ // From int to sbyte, byte, short, ushort, uint, ulong, char, uintptr
//
if (real_target_type == TypeManager.sbyte_type)
return new ConvCast (expr, target_type, ConvCast.Mode.I4_I1);
return new ConvCast (expr, target_type, ConvCast.Mode.I4_U8);
if (real_target_type == TypeManager.char_type)
return new ConvCast (expr, target_type, ConvCast.Mode.I4_CH);
+
+ // One of the built-in conversions that belonged in the class library
+ if (real_target_type == TypeManager.uintptr_type){
+ Expression u8e = new ConvCast (expr, TypeManager.uint64_type, ConvCast.Mode.I2_U8);
+
+ return new OperatorCast (u8e, TypeManager.uintptr_type, true);
+ }
} else if (expr_type == TypeManager.uint32_type){
//
// From uint to sbyte, byte, short, ushort, int, char
return new ConvCast (expr, target_type, ConvCast.Mode.U8_I8);
if (real_target_type == TypeManager.char_type)
return new ConvCast (expr, target_type, ConvCast.Mode.U8_CH);
+
+ // One of the built-in conversions that belonged in the class library
+ if (real_target_type == TypeManager.intptr_type){
+ return new OperatorCast (new EmptyCast (expr, TypeManager.int64_type),
+ TypeManager.intptr_type, true);
+ }
} else if (expr_type == TypeManager.char_type){
//
// From char to sbyte, byte, short
return new ConvCast (expr, target_type, ConvCast.Mode.R8_R4);
if (real_target_type == TypeManager.decimal_type)
return new CastToDecimal (expr, true);
+ } else if (expr_type == TypeManager.uintptr_type){
+ //
+ // Various built-in conversions that belonged in the class library
+ //
+ // from uintptr to sbyte, short, int32
+ //
+ if (real_target_type == TypeManager.sbyte_type){
+ Expression uint32e = new OperatorCast (expr, TypeManager.uint32_type, true);
+ return new ConvCast (uint32e, TypeManager.sbyte_type, ConvCast.Mode.U4_I1);
+ }
+ if (real_target_type == TypeManager.short_type){
+ Expression uint32e = new OperatorCast (expr, TypeManager.uint32_type, true);
+ return new ConvCast (uint32e, TypeManager.sbyte_type, ConvCast.Mode.U4_I2);
+ }
+ if (real_target_type == TypeManager.int32_type){
+ return new EmptyCast (new OperatorCast (expr, TypeManager.uint32_type, true),
+ TypeManager.int32_type);
+ }
+ } else if (expr_type == TypeManager.intptr_type){
+ if (real_target_type == TypeManager.uint64_type){
+ return new EmptyCast (new OperatorCast (expr, TypeManager.int64_type, true),
+ TypeManager.uint64_type);
+ }
} else if (expr_type == TypeManager.decimal_type) {
return new CastFromDecimal (expr, target_type).Resolve ();
}
/// </summary>
public static bool ExplicitReferenceConversionExists (Type source_type, Type target_type)
{
+ bool target_is_type_param = TypeManager.IsGenericParameter (target_type);
bool target_is_value_type = target_type.IsValueType;
-
+
if (source_type == target_type)
return true;
-
+
+ //
+ // From generic parameter to any type
+ //
+ if (TypeManager.IsGenericParameter (source_type))
+ return ExplicitTypeParameterConversionExists (source_type, target_type);
+
+ //
+ // From object to a generic parameter
+ //
+ if (source_type == TypeManager.object_type && target_is_type_param)
+ return true;
+
//
// From object to any reference type
//
if (source_type == TypeManager.object_type && !target_is_value_type)
return true;
-
+
//
// From any class S to any class-type T, provided S is a base class of T
//
- if (target_type.IsSubclassOf (source_type))
+ if (TypeManager.IsSubclassOf (target_type, source_type))
return true;
//
// From any interface type S to any interface T provided S is not derived from T
//
if (source_type.IsInterface && target_type.IsInterface){
- if (!target_type.IsSubclassOf (source_type))
+ if (!TypeManager.IsSubclassOf (target_type, source_type))
return true;
}
-
+
//
// From any class type S to any interface T, provided S is not sealed
// and provided S does not implement T.
if (source_type.IsInterface &&
(!target_type.IsSealed || TypeManager.ImplementsInterface (target_type, source_type)))
return true;
-
-
- // From an array type S with an element type Se to an array type T with an
+
+
+ // From an array type S with an element type Se to an array type T with an
// element type Te provided all the following are true:
// * S and T differe only in element type, in other words, S and T
// have the same number of dimensions.
//
if (source_type.IsArray && target_type.IsArray) {
if (source_type.GetArrayRank () == target_type.GetArrayRank ()) {
-
+
Type source_element_type = TypeManager.GetElementType (source_type);
Type target_element_type = TypeManager.GetElementType (target_type);
-
- if (!source_element_type.IsValueType && !target_element_type.IsValueType)
+
+ if (TypeManager.IsGenericParameter (source_element_type) ||
+ (!source_element_type.IsValueType && !target_element_type.IsValueType))
if (ExplicitReferenceConversionExists (source_element_type,
target_element_type))
return true;
}
}
-
+
// From System.Array to any array-type
if (source_type == TypeManager.array_type &&
// From System delegate to any delegate-type
//
if (source_type == TypeManager.delegate_type &&
- target_type.IsSubclassOf (TypeManager.delegate_type))
+ TypeManager.IsDelegateType (target_type))
return true;
//
(target_type == TypeManager.array_type ||
target_type == TypeManager.delegate_type))
return true;
-
+
return false;
}
static Expression ExplicitReferenceConversion (Expression source, Type target_type)
{
Type source_type = source.Type;
+ bool target_is_type_param = TypeManager.IsGenericParameter (target_type);
bool target_is_value_type = target_type.IsValueType;
+ //
+ // From object to a generic parameter
+ //
+ if (source_type == TypeManager.object_type && target_is_type_param)
+ return new UnboxCast (source, target_type);
+
+ //
+ // Explicit type parameter conversion.
+ //
+
+ if (TypeManager.IsGenericParameter (source_type))
+ return ExplicitTypeParameterConversion (source, target_type);
+
//
// From object to any reference type
//
//
// From any class S to any class-type T, provided S is a base class of T
//
- if (target_type.IsSubclassOf (source_type))
+ if (TypeManager.IsSubclassOf (target_type, source_type))
return new ClassCast (source, target_type);
//
else
return new ClassCast (source, target_type);
}
-
+
//
// From any class type S to any interface T, provides S is not sealed
// and provided S does not implement T.
return null;
else
return new ClassCast (source, target_type);
-
+
}
//
return null;
}
-
- // From an array type S with an element type Se to an array type T with an
+
+ // From an array type S with an element type Se to an array type T with an
// element type Te provided all the following are true:
// * S and T differe only in element type, in other words, S and T
// have the same number of dimensions.
//
if (source_type.IsArray && target_type.IsArray) {
if (source_type.GetArrayRank () == target_type.GetArrayRank ()) {
-
+
Type source_element_type = TypeManager.GetElementType (source_type);
Type target_element_type = TypeManager.GetElementType (target_type);
-
+
if (!source_element_type.IsValueType && !target_element_type.IsValueType)
if (ExplicitReferenceConversionExists (source_element_type,
target_element_type))
return new ClassCast (source, target_type);
}
}
-
+
// From System.Array to any array-type
if (source_type == TypeManager.array_type &&
// From System delegate to any delegate-type
//
if (source_type == TypeManager.delegate_type &&
- target_type.IsSubclassOf (TypeManager.delegate_type))
+ TypeManager.IsDelegateType (target_type))
return new ClassCast (source, target_type);
//
(target_type == TypeManager.array_type ||
target_type == TypeManager.delegate_type))
return new ClassCast (source, target_type);
-
+
return null;
}
-
+
/// <summary>
/// Performs an explicit conversion of the expression `expr' whose
/// type is expr.Type to `target_type'.
/// </summary>
static public Expression ExplicitConversionCore (EmitContext ec, Expression expr,
- Type target_type, Location loc)
+ Type target_type, Location loc)
{
Type expr_type = expr.Type;
//
// Unboxing conversions; only object types can be convertible to enum
//
- if (expr_type == TypeManager.object_type && target_type.IsValueType || expr_type == TypeManager.enum_type)
+ if (expr_type == TypeManager.object_type && target_type.IsValueType)
return new UnboxCast (expr, target_type);
if (TypeManager.IsEnumType (expr_type)) {
return ExplicitConversionCore (ec, new EmptyCast (expr, TypeManager.EnumToUnderlying (expr_type)), target_type, loc);
}
- if (TypeManager.IsEnumType (target_type))
- return new EmptyCast (ExplicitConversionCore (ec, expr, TypeManager.EnumToUnderlying (target_type), loc), target_type);
+ if (TypeManager.IsEnumType (target_type)){
+ if (expr_type == TypeManager.enum_type)
+ return new UnboxCast (expr, target_type);
+
+ Expression ce = ExplicitConversionCore (ec, expr, TypeManager.EnumToUnderlying (target_type), loc);
+ if (ce != null)
+ return new EmptyCast (ce, target_type);
+ }
ne = ExplicitNumericConversion (expr, target_type);
if (ne != null)
if (target_type.IsPointer){
if (expr_type.IsPointer)
return new EmptyCast (expr, target_type);
-
+
if (expr_type == TypeManager.sbyte_type ||
expr_type == TypeManager.short_type ||
expr_type == TypeManager.int32_type ||
/// Same as ExplicitConversion, only it doesn't include user defined conversions
/// </summary>
static public Expression ExplicitConversionStandard (EmitContext ec, Expression expr,
- Type target_type, Location l)
+ Type target_type, Location l)
{
+ int errors = Report.Errors;
Expression ne = ImplicitConversionStandard (ec, expr, target_type, l);
+ if (Report.Errors > errors)
+ return null;
+
if (ne != null)
return ne;
if (ec.InUnsafe && expr.Type == TypeManager.void_ptr_type && target_type.IsPointer)
return new EmptyCast (expr, target_type);
- expr.Error_ValueCannotBeConverted (l, target_type, true);
+ expr.Error_ValueCannotBeConverted (ec, l, target_type, true);
return null;
}
static public Expression ExplicitConversion (EmitContext ec, Expression expr,
Type target_type, Location loc)
{
- Expression e = ExplicitConversionCore (ec, expr, target_type, loc);
+ Expression e;
+#if GMCS_SOURCE
+ Type expr_type = expr.Type;
+ if (TypeManager.IsNullableType (target_type)) {
+ if (TypeManager.IsNullableType (expr_type)) {
+ e = new Nullable.LiftedConversion (
+ expr, target_type, false, true, loc).Resolve (ec);
+ if (e != null)
+ return e;
+ } else if (expr_type == TypeManager.object_type) {
+ return new UnboxCast (expr, target_type);
+ } else {
+ Type target = TypeManager.GetTypeArguments (target_type) [0];
+
+ e = ExplicitConversionCore (ec, expr, target, loc);
+ if (e != null)
+ return Nullable.Wrap.Create (e, ec);
+ }
+ } else if (TypeManager.IsNullableType (expr_type)) {
+ Expression source = Nullable.Unwrap.Create (expr, ec);
+ if (source != null) {
+ e = ExplicitConversionCore (ec, source, target_type, loc);
+ if (e != null)
+ return e;
+ }
+ }
+#endif
+ e = ExplicitConversionCore (ec, expr, target_type, loc);
if (e != null)
return e;
- expr.Error_ValueCannotBeConverted (loc, target_type, true);
+ expr.Error_ValueCannotBeConverted (ec, loc, target_type, true);
return null;
}
}