[Question] Is UFCS supposed to use ADL?

[guybrush77]

Sorry if this had been asked before, but is UFCS supposed to use ADL? For example:

foo: namespace = {
    print: (i: int) = std::cout << i << "\n";
}

main: () = {
    i := 42;
    i.print();
}

[JohelEGP]

Depends on what you mean by "suppose".
It can use ADL.
But it doesn't have to.
AFAIK, UFCS is simply defined as 𝘰𝘣𝘫.𝘧(𝘢𝘳𝘨𝘴) if that is well-formed, and 𝘧(𝘰𝘣𝘫, 𝘢𝘳𝘨𝘴) otherwise.
So by definition of the Cpp1 semantics of (non-member) function call, it can use ADL.

[guybrush77]

I see. In that case, the example above will not work because, under current rules, the compiler won't try to generate foo::print(i).

Perhaps this is a naive question, but if we had true ADL lookup in the core language, could this be made to work? Though perhaps it might open a can of worms...

[JohelEGP]

Yes, because that's not ADL.
Fundamental types don't have an associated namespace.