//
// Note: C# specification null-literal is NullLiteral of NullType type
//
- class NullLiteral : Constant
+ public class NullLiteral : NullConstant
{
//
// Default type of null is an object
//
- public NullLiteral (Location loc):
- this (typeof (NullLiteral), loc)
+ public NullLiteral (Location loc)
+ : base (InternalType.Null, loc)
{
}
- //
- // Null can have its own type, think of default (Foo)
- //
- public NullLiteral (Type type, Location loc)
- : base (loc)
- {
- eclass = ExprClass.Value;
- this.type = type;
- }
-
- override public string AsString ()
- {
- return GetSignatureForError ();
- }
-
- public override Expression CreateExpressionTree (EmitContext ec)
- {
- // HACK: avoid referencing mcs internal type
- if (type == typeof (NullLiteral))
- type = TypeManager.object_type;
-
- return base.CreateExpressionTree (ec);
- }
-
- public override Expression DoResolve (EmitContext ec)
- {
- return this;
- }
-
- public override void Emit (EmitContext ec)
- {
- ec.ig.Emit (OpCodes.Ldnull);
-
-#if GMCS_SOURCE
- // Only to make verifier happy
- if (TypeManager.IsGenericParameter (type))
- ec.ig.Emit (OpCodes.Unbox_Any, type);
-#endif
- }
-
- public override string ExprClassName {
- get {
- return GetSignatureForError ();
- }
- }
-
- public override string GetSignatureForError ()
- {
- return "null";
- }
-
- public override void Error_ValueCannotBeConverted (EmitContext ec, Location loc, Type t, bool expl)
+ public override void Error_ValueCannotBeConverted (ResolveContext ec, Location loc, TypeSpec t, bool expl)
{
- if (TypeManager.IsGenericParameter (t)) {
- Report.Error(403, loc,
+ if (t.IsGenericParameter) {
+ ec.Report.Error(403, loc,
"Cannot convert null to the type parameter `{0}' because it could be a value " +
"type. Consider using `default ({0})' instead", t.Name);
return;
}
if (TypeManager.IsValueType (t)) {
- Report.Error(37, loc, "Cannot convert null to `{0}' because it is a value type",
+ ec.Report.Error(37, loc, "Cannot convert null to `{0}' because it is a value type",
TypeManager.CSharpName(t));
return;
}
base.Error_ValueCannotBeConverted (ec, loc, t, expl);
}
- public override Constant ConvertExplicitly (bool inCheckedContext, Type targetType)
- {
- if (targetType.IsPointer) {
- if (type == TypeManager.null_type || this is NullPointer)
- return new EmptyConstantCast (new NullPointer (loc), targetType);
-
- return null;
- }
-
- // Exlude internal compiler types
- if (targetType == TypeManager.anonymous_method_type)
- return null;
-
- if (TypeManager.IsReferenceType (targetType))
- return new NullLiteral (targetType, loc);
-
- if (TypeManager.IsNullableType (targetType))
- return Nullable.LiftedNull.Create (targetType, loc);
-
- return null;
- }
-
- public override Constant ConvertImplicitly (Type targetType)
- {
- //
- // Null literal is of object type
- //
- if (targetType == TypeManager.object_type)
- return this;
-
- return ConvertExplicitly (false, targetType);
- }
-
- public override object GetValue ()
- {
- return null;
- }
-
- public override Constant Increment ()
- {
- throw new NotSupportedException ();
- }
-
- public override bool IsDefaultValue {
- get { return true; }
- }
-
public override bool IsLiteral {
get { return true; }
}
- public override bool IsNegative {
- get { return false; }
- }
-
- public override bool IsNull {
- get { return true; }
- }
-
- public override bool IsZeroInteger {
- get { return true; }
+ public override System.Linq.Expressions.Expression MakeExpression (BuilderContext ctx)
+ {
+ return System.Linq.Expressions.Expression.Constant (null);
}
}
public override void Emit (EmitContext ec)
{
- ILGenerator ig = ec.ig;
-
//
// Emits null pointer
//
- ig.Emit (OpCodes.Ldc_I4_0);
- ig.Emit (OpCodes.Conv_U);
+ ec.Emit (OpCodes.Ldc_I4_0);
+ ec.Emit (OpCodes.Conv_U);
}
}
{
}
- public override Expression DoResolve (EmitContext ec)
- {
- type = TypeManager.bool_type;
- return this;
- }
-
public override bool IsLiteral {
get { return true; }
}
{
}
- public override Expression DoResolve (EmitContext ec)
- {
- type = TypeManager.char_type;
- return this;
- }
-
public override bool IsLiteral {
get { return true; }
}
{
}
- public override Expression DoResolve (EmitContext ec)
+ public override Constant ConvertImplicitly (ResolveContext rc, TypeSpec type)
{
- type = TypeManager.int32_type;
- return this;
- }
-
- public override Constant ConvertImplicitly (Type type)
- {
- ///
- /// The 0 literal can be converted to an enum value,
- ///
+ //
+ // The 0 literal can be converted to an enum value
+ //
if (Value == 0 && TypeManager.IsEnumType (type)) {
- Constant c = ConvertImplicitly (TypeManager.GetEnumUnderlyingType (type));
+ Constant c = ConvertImplicitly (rc, EnumSpec.GetUnderlyingType (type));
if (c == null)
return null;
- return new EnumConstant (c, type);
+ return new EnumConstant (c, type).Resolve (rc);
}
- return base.ConvertImplicitly (type);
+
+ return base.ConvertImplicitly (rc, type);
}
public override bool IsLiteral {
{
}
- public override Expression DoResolve (EmitContext ec)
- {
- type = TypeManager.uint32_type;
- return this;
- }
-
public override bool IsLiteral {
get { return true; }
}
{
}
- public override Expression DoResolve (EmitContext ec)
- {
- type = TypeManager.int64_type;
- return this;
- }
-
public override bool IsLiteral {
get { return true; }
}
{
}
- public override Expression DoResolve (EmitContext ec)
- {
- type = TypeManager.uint64_type;
- return this;
- }
-
public override bool IsLiteral {
get { return true; }
}
{
}
- public override Expression DoResolve (EmitContext ec)
- {
- type = TypeManager.float_type;
- return this;
- }
-
public override bool IsLiteral {
get { return true; }
}
{
}
- public override Expression DoResolve (EmitContext ec)
- {
- type = TypeManager.double_type;
-
- return this;
- }
-
- public override void Error_ValueCannotBeConverted (EmitContext ec, Location loc, Type target, bool expl)
+ public override void Error_ValueCannotBeConverted (ResolveContext ec, Location loc, TypeSpec target, bool expl)
{
if (target == TypeManager.float_type) {
- Error_664 (loc, "float", "f");
+ Error_664 (ec, loc, "float", "f");
return;
}
if (target == TypeManager.decimal_type) {
- Error_664 (loc, "decimal", "m");
+ Error_664 (ec, loc, "decimal", "m");
return;
}
base.Error_ValueCannotBeConverted (ec, loc, target, expl);
}
- static void Error_664 (Location loc, string type, string suffix)
+ static void Error_664 (ResolveContext ec, Location loc, string type, string suffix)
{
- Report.Error (664, loc,
+ ec.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);
}
{
}
- public override Expression DoResolve (EmitContext ec)
- {
- type = TypeManager.decimal_type;
- return this;
- }
-
public override bool IsLiteral {
get { return true; }
}
{
}
- public override Expression DoResolve (EmitContext ec)
- {
- type = TypeManager.string_type;
-
- return this;
- }
-
public override bool IsLiteral {
get { return true; }
}
projects / mono.git / blobdiff