public static UnaryOperatorSymbol ClassifyOperation(UnaryOperatorKind kind, TypeSymbol expr)
{
int exprIdx = ConversionEasyOut.TypeToIndex(expr);
if (exprIdx < 0)
{
return(null);
}
return(s_unOp[(int)kind][exprIdx]);
}
public static BinaryOperatorSymbol ClassifyOperation(BinaryOperatorKind kind, TypeSymbol left, TypeSymbol right)
{
int leftIdx = ConversionEasyOut.TypeToIndex(left);
if (leftIdx < 0)
{
return(null);
}
int rightIdx = ConversionEasyOut.TypeToIndex(right);
if (rightIdx < 0)
{
return(null);
}
return(s_binOp[(int)kind][leftIdx, rightIdx]);
}
internal static ConversionSymbol Conversion(Expr expr, TypeSymbol type, BindOptions options)
{
var noConversion = ConversionKind.NoConversion;
var conversion = ConversionEasyOut.ClassifyConversion(expr.Datatype, type);
if (expr.Symbol.IsConstant() || expr.IsConstant)
{
options |= BindOptions.Explicit;
}
if (conversion != ConversionKind.NoConversion)
{
var conv = ConversionSymbol.Create(conversion);
if (!conv.IsCast && options.HasFlag(BindOptions.Explicit) || conv.IsImplicit)
{
return(conv);
}
if (conv.IsCast && options.HasFlag(BindOptions.Cast))
{
return(conv);
}
if (conv.IsExplicit && conv.Kind == ConversionKind.ExplicitNumeric && options.HasFlag(BindOptions.AllowImplicitNarrowingConversions))
{
return(conv); // TODO nvk: this should raise a warning!
}
if (conv.Exists)
{
noConversion = ConversionKind.NoImplicitConversion;
}
}
if (TypesMatch(expr.Datatype, type))
{
return(ConversionSymbol.Create(ConversionKind.Identity));
}
if (type.Type.IsGenericType || expr.Datatype.Type.IsGenericType)
{
return(ConversionSymbol.Create(noConversion));
}
MethodSymbol converter = null;
ResolveUserDefinedConversion(expr, type, expr.Datatype.Lookup(OperatorNames.Implicit), type.Lookup(OperatorNames.Implicit), ref converter, options | BindOptions.Special);
if (converter != null)
{
return(ConversionSymbol.Create(ConversionKind.ImplicitUserDefined, converter));
}
if (options.HasFlag(BindOptions.Explicit))
{
ResolveUserDefinedConversion(expr, type, expr.Datatype.Lookup(OperatorNames.Explicit), type.Lookup(OperatorNames.Explicit), ref converter, options | BindOptions.Special);
if (converter != null)
{
return(ConversionSymbol.Create(ConversionKind.ExplicitUserDefined, converter));
}
}
{
var conv = ResolveUsualConversion(expr, type, options);
if (conv != null)
{
return(conv);
}
}
if (type.IsByRef != expr.Datatype.IsByRef)
{
var conv = ResolveByRefConversion(expr, type, options);
if (conv != null)
{
return(conv);
}
}
if (type.NativeType == NativeType.Object)
{
if (expr.Datatype.Type.IsValueType)
{
return(ConversionSymbol.Create(ConversionKind.Boxing));
}
else
{
return(ConversionSymbol.Create(ConversionKind.ImplicitReference));
}
}
else if (expr.Datatype.NativeType == NativeType.Object)
{
if (!options.HasFlag(BindOptions.AllowDynamic))
{
if (options.HasFlag(BindOptions.Explicit))
{
return(type.IsValueType ? ConversionSymbol.Create(ConversionKind.Unboxing) : ConversionSymbol.Create(ConversionKind.ExplicitReference));
}
else
{
noConversion = ConversionKind.NoImplicitConversion;
}
}
}
else if (type.IsReferenceType && expr.Datatype.IsReferenceType)
{
if (expr.Datatype.IsSubclassOf(type))
{
return(ConversionSymbol.Create(ConversionKind.ImplicitReference));
}
if (type.IsSubclassOf(expr.Datatype))
{
if (options.HasFlag(BindOptions.Explicit))
{
return(ConversionSymbol.Create(ConversionKind.ExplicitReference));
}
else
{
noConversion = ConversionKind.NoImplicitConversion;
}
}
}
{
var conv = ResolveEnumConversion(expr, type, options);
if (conv != null)
{
return(conv);
}
}
if (options.HasFlag(BindOptions.AllowDynamic))
{
var conv = ResolveDynamicConversion(expr, type, options);
if (conv != null)
{
return(conv);
}
}
if (!options.HasFlag(BindOptions.Explicit) && noConversion == ConversionKind.NoConversion)
{
ResolveUserDefinedConversion(expr, type, expr.Datatype.Lookup(OperatorNames.Explicit), type.Lookup(OperatorNames.Explicit), ref converter, options | BindOptions.Special);
if (converter != null)
{
noConversion = ConversionKind.NoImplicitConversion;
}
}
return(ConversionSymbol.Create(noConversion));
}
