inline virtual To eval()
{
cached_number = Converter::do_conv(from_expr->eval());
// Here we may be returning a reference to the cached value instead of by-value.
return cached_number;
}
virtual IoObject* eval_in_context(IoObject *self, IoObject *locals, IoMessage *m)
{
return F::eval_in_context(self, locals, m, from_expr->eval());
}