source: branches/2817-BinPackingSpeedup/HeuristicLab.ExtLibs/HeuristicLab.NRefactory/5.5.0/NRefactory.CSharp-5.5.0/Parser/mcs/literal.cs

//
// literal.cs: Literal representation for the IL tree.
//
// Author:
//   Miguel de Icaza (miguel@ximian.com)
//   Marek Safar (marek.safar@seznam.cz)
//
// Copyright 2001 Ximian, Inc.
// Copyright 2011 Xamarin 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.
//

#if STATIC
using IKVM.Reflection.Emit;
#else
using System.Reflection.Emit;
#endif

namespace Mono.CSharp
{
  public interface ILiteralConstant
  {
#if FULL_AST
    char[] ParsedValue { get; set; }
#endif
  }

  //
  // The null literal
  //
  // Note: C# specification null-literal is NullLiteral of NullType type
  //
  public class NullLiteral : NullConstant
  {
    //
    // Default type of null is an object
    //
    public NullLiteral (Location loc)
      : base (InternalType.NullLiteral, loc)
    {
    }

    public override void Error_ValueCannotBeConverted (ResolveContext ec, TypeSpec t, bool expl)
    {
      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 (TypeSpec.IsValueType (t)) {
        ec.Report.Error(37, loc, "Cannot convert null to `{0}' because it is a value type",
          t.GetSignatureForError ());
        return;
      }

      base.Error_ValueCannotBeConverted (ec, t, expl);
    }

    public override string GetValueAsLiteral ()
    {
      return "null";
    }

    public override bool IsLiteral {
      get { return true; }
    }

    public override System.Linq.Expressions.Expression MakeExpression (BuilderContext ctx)
    {
      return System.Linq.Expressions.Expression.Constant (null);
    }
  }

  public class BoolLiteral : BoolConstant, ILiteralConstant
  {
    public BoolLiteral (BuiltinTypes types, bool val, Location loc)
      : base (types, val, loc)
    {
    }

    public override bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }

  public class CharLiteral : CharConstant, ILiteralConstant
  {
    public CharLiteral (BuiltinTypes types, char c, Location loc)
      : base (types, c, loc)
    {
    }

    public override bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }

  public class IntLiteral : IntConstant, ILiteralConstant
  {
    public IntLiteral (BuiltinTypes types, int l, Location loc)
      : base (types, l, loc)
    {
    }

    public override Constant ConvertImplicitly (TypeSpec type)
    {
      //
      // The 0 literal can be converted to an enum value
      //
      if (Value == 0 && type.IsEnum) {
        Constant c = ConvertImplicitly (EnumSpec.GetUnderlyingType (type));
        if (c == null)
          return null;

        return new EnumConstant (c, type);
      }

      return base.ConvertImplicitly (type);
    }

    public override bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }

  public class UIntLiteral : UIntConstant, ILiteralConstant
  {
    public UIntLiteral (BuiltinTypes types, uint l, Location loc)
      : base (types, l, loc)
    {
    }

    public override bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }

  public class LongLiteral : LongConstant, ILiteralConstant
  {
    public LongLiteral (BuiltinTypes types, long l, Location loc)
      : base (types, l, loc)
    {
    }

    public override bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }

  public class ULongLiteral : ULongConstant, ILiteralConstant
  {
    public ULongLiteral (BuiltinTypes types, ulong l, Location loc)
      : base (types, l, loc)
    {
    }

    public override bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }

  public class FloatLiteral : FloatConstant, ILiteralConstant
  {
    public FloatLiteral (BuiltinTypes types, float f, Location loc)
      : base (types, f, loc)
    {
    }

    public override bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }

  public class DoubleLiteral : DoubleConstant, ILiteralConstant
  {
    public DoubleLiteral (BuiltinTypes types, double d, Location loc)
      : base (types, d, loc)
    {
    }

    public override void Error_ValueCannotBeConverted (ResolveContext ec, TypeSpec target, bool expl)
    {
      if (target.BuiltinType == BuiltinTypeSpec.Type.Float) {
        Error_664 (ec, loc, "float", "f");
        return;
      }

      if (target.BuiltinType == BuiltinTypeSpec.Type.Decimal) {
        Error_664 (ec, loc, "decimal", "m");
        return;
      }

      base.Error_ValueCannotBeConverted (ec, target, expl);
    }

    static void Error_664 (ResolveContext ec, Location loc, string type, string suffix)
    {
      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 bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }

  public class DecimalLiteral : DecimalConstant, ILiteralConstant
  {
    public DecimalLiteral (BuiltinTypes types, decimal d, Location loc)
      : base (types, d, loc)
    {
    }

    public override bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }

  public class StringLiteral : StringConstant, ILiteralConstant
  {
    public StringLiteral (BuiltinTypes types, string s, Location loc)
      : base (types, s, loc)
    {
    }

    public override bool IsLiteral {
      get { return true; }
    }

#if FULL_AST
    public char[] ParsedValue { get; set; }
#endif

    public override object Accept (StructuralVisitor visitor)
    {
      return visitor.Visit (this);
    }
  }
}