2 // literal.cs: Literal representation for the IL tree.
5 // Miguel de Icaza (miguel@ximian.com)
6 // Marek Safar (marek.safar@seznam.cz)
8 // Copyright 2001 Ximian, Inc.
11 // Notice that during parsing we create objects of type Literal, but the
12 // types are not loaded (thats why the Resolve method has to assign the
13 // type at that point).
15 // Literals differ from the constants in that we know we encountered them
16 // as a literal in the source code (and some extra rules apply there) and
17 // they have to be resolved (since during parsing we have not loaded the
18 // types yet) while constants are created only after types have been loaded
19 // and are fully resolved when born.
23 using System.Reflection;
24 using System.Reflection.Emit;
26 namespace Mono.CSharp {
31 // Note: C# specification null-literal is NullLiteral of NullType type
33 public class NullLiteral : NullConstant
36 // Default type of null is an object
38 public NullLiteral (Location loc)
39 : base (InternalType.Null, loc)
43 public override void Error_ValueCannotBeConverted (ResolveContext ec, Location loc, TypeSpec t, bool expl)
45 if (t.IsGenericParameter) {
46 ec.Report.Error(403, loc,
47 "Cannot convert null to the type parameter `{0}' because it could be a value " +
48 "type. Consider using `default ({0})' instead", t.Name);
52 if (TypeManager.IsValueType (t)) {
53 ec.Report.Error(37, loc, "Cannot convert null to `{0}' because it is a value type",
54 TypeManager.CSharpName(t));
58 base.Error_ValueCannotBeConverted (ec, loc, t, expl);
61 public override bool IsLiteral {
65 public override System.Linq.Expressions.Expression MakeExpression (BuilderContext ctx)
67 return System.Linq.Expressions.Expression.Constant (null);
72 // A null literal in a pointer context
74 class NullPointer : NullLiteral {
75 public NullPointer (Location loc):
78 type = TypeManager.object_type;
81 public override void Emit (EmitContext ec)
86 ec.Emit (OpCodes.Ldc_I4_0);
87 ec.Emit (OpCodes.Conv_U);
91 public class BoolLiteral : BoolConstant {
92 public BoolLiteral (bool val, Location loc) : base (val, loc)
96 public override bool IsLiteral {
101 public class CharLiteral : CharConstant {
102 public CharLiteral (char c, Location loc) : base (c, loc)
106 public override bool IsLiteral {
111 public class IntLiteral : IntConstant {
112 public IntLiteral (int l, Location loc) : base (l, loc)
116 public override Constant ConvertImplicitly (ResolveContext rc, TypeSpec type)
119 // The 0 literal can be converted to an enum value
121 if (Value == 0 && TypeManager.IsEnumType (type)) {
122 Constant c = ConvertImplicitly (rc, EnumSpec.GetUnderlyingType (type));
126 return new EnumConstant (c, type).Resolve (rc);
129 return base.ConvertImplicitly (rc, type);
132 public override bool IsLiteral {
137 public class UIntLiteral : UIntConstant {
138 public UIntLiteral (uint l, Location loc) : base (l, loc)
142 public override bool IsLiteral {
147 public class LongLiteral : LongConstant {
148 public LongLiteral (long l, Location loc) : base (l, loc)
152 public override bool IsLiteral {
157 public class ULongLiteral : ULongConstant {
158 public ULongLiteral (ulong l, Location loc) : base (l, loc)
162 public override bool IsLiteral {
167 public class FloatLiteral : FloatConstant {
169 public FloatLiteral (float f, Location loc) : base (f, loc)
173 public override bool IsLiteral {
179 public class DoubleLiteral : DoubleConstant {
180 public DoubleLiteral (double d, Location loc) : base (d, loc)
184 public override void Error_ValueCannotBeConverted (ResolveContext ec, Location loc, TypeSpec target, bool expl)
186 if (target == TypeManager.float_type) {
187 Error_664 (ec, loc, "float", "f");
191 if (target == TypeManager.decimal_type) {
192 Error_664 (ec, loc, "decimal", "m");
196 base.Error_ValueCannotBeConverted (ec, loc, target, expl);
199 static void Error_664 (ResolveContext ec, Location loc, string type, string suffix)
201 ec.Report.Error (664, loc,
202 "Literal of type double cannot be implicitly converted to type `{0}'. Add suffix `{1}' to create a literal of this type",
206 public override bool IsLiteral {
212 public class DecimalLiteral : DecimalConstant {
213 public DecimalLiteral (decimal d, Location loc) : base (d, loc)
217 public override bool IsLiteral {
222 public class StringLiteral : StringConstant {
223 public StringLiteral (string s, Location loc) : base (s, loc)
227 public override bool IsLiteral {