internal static Expression ExplicitConvert(Expression /*!*/ expr, Type /*!*/ fromType, Type /*!*/ toType)
{
expr = AstUtils.Convert(expr, fromType);
if (HasExplicitNumericConversion(fromType, toType))
{
// special cases to mimic Ruby behavior precisely:
if (fromType == typeof(BigInteger))
{
if (toType == typeof(int))
{
return(Methods.ConvertBignumToFixnum.OpCall(expr));
}
else if (toType == typeof(double))
{
return(Methods.ConvertBignumToFloat.OpCall(expr));
}
}
else if (fromType == typeof(double) && toType == typeof(int))
{
return(Methods.ConvertDoubleToFixnum.OpCall(expr));
}
return(Ast.ConvertChecked(expr, toType));
}
MethodInfo converter = CompilerHelpers.GetExplicitConverter(fromType, toType);
if (converter != null)
{
return(Ast.Call(null, converter, expr));
}
if (fromType == typeof(char) && toType == typeof(string))
{
return(Ast.Call(null, fromType.GetMethod("ToString", BindingFlags.Public | BindingFlags.Static), expr));
}
if (toType == typeof(bool))
{
Debug.Assert(fromType != typeof(bool));
return(fromType.IsValueType ? AstUtils.Constant(true) : Ast.NotEqual(expr, AstUtils.Constant(null)));
}
// TODO:
//if (TypeConverter...(fromType, toType)) {
// return true;
//}
return(null);
}