Andrei Alexandrescu wrote:
Don wrote:
Not necessarily. Andrei can just add:
static if(__traits(compiles, mixin(comp) )) {
mixin(comp);
} else {
// static assert is a bit broken,
// better to do it this way to provide a backtrace.
pragma(msg, "Bad predicate: " ~ comp);
deliberate_error_message; // t
}
into std.functional. Which will generate a very controlled error message.
(Doesn't work if the predicate contains mismatched parentheses, but
that's fixable).
I tried the above and didn't quite work. The deliberate_error_message
would trigger an error even for valid expressions. What I have now is this:
Use a string mixin for deliberate_error_message.
