ResolveResult CastTo(TypeCode targetType, bool isNullable, ResolveResult expression, bool allowNullableConstants)
{
IType elementType = compilation.FindType(targetType);
IType nullableType = MakeNullable(elementType, isNullable);
if (nullableType.Equals(expression.Type))
return expression;
if (allowNullableConstants && expression.IsCompileTimeConstant) {
if (expression.ConstantValue == null)
return new ConstantResolveResult(nullableType, null);
ResolveResult rr = ResolveCast(elementType, expression);
if (rr.IsError)
return rr;
Debug.Assert(rr.IsCompileTimeConstant);
return new ConstantResolveResult(nullableType, rr.ConstantValue);
} else {
return Convert(expression, nullableType,
isNullable ? Conversion.ImplicitNullableConversion : Conversion.ImplicitNumericConversion);
}
}
#endregion
