private OverloadResolutionResult <FunctionSymbolSignature> LookupFunction(SyntaxToken name, ImmutableArray <Type> argumentTypes)
{
var signatures = from f in LookupSymbols <FunctionSymbol>(name)
where name.Matches(f.Name)
select new FunctionSymbolSignature(f);
return(OverloadResolution.Perform(signatures, argumentTypes));
}
private OverloadResolutionResult <MethodSymbolSignature> LookupMethod(Type type, SyntaxToken name, ImmutableArray <Type> argumentTypes)
{
if (name == null)
{
throw new ArgumentNullException(nameof(name));
}
var signatures = from m in LookupMethod(type, name)
select new MethodSymbolSignature(m);
return(OverloadResolution.Perform(signatures, argumentTypes));
}
internal static OverloadResolutionResult <UnaryOperatorSignature> Resolve(UnaryOperatorKind kind, Type type)
{
var builtInSignatures = GetBuiltInSignatures(kind);
// If the type is built-in, we can simply perform the overload resolution
// against the built-in signatures only.
if (TypeBuiltIn(type))
{
return(OverloadResolution.Perform(builtInSignatures, type));
}
// Otherwise, we need to consider user defined signatures.
//
// NOTE: We generally want to perform an overload resolution against the unified
// set of both, built-in signatures as well as user defined signatures.
// However, if the type provides an operator that is applicable, we want to
// to hide the built-in operators. In other words, in those cases the user
// defined operators shadows the built-in operators.
// Please note that we don't ask whether the overload resolution found a
// best match -- we just check if it has an applicable operator. This makes
// sure that any any ambiguity errors will not include built-in operators
// in the output.
var userDefinedSignatures = GetUserDefinedSignatures(kind, type);
if (userDefinedSignatures.Any())
{
var userDefinedResult = OverloadResolution.Perform(userDefinedSignatures, type);
if (userDefinedResult.Candidates.Any(c => c.IsApplicable))
{
return(userDefinedResult);
}
}
var signatures = builtInSignatures.Concat(userDefinedSignatures);
return(OverloadResolution.Perform(signatures, type));
}
