Handle ReEarlyParam in type_name.

[nnethercote]

Fixes #145696.

r? @lcnr

[rustbot]

Some changes occurred to the CTFE machinery

cc @RalfJung, @oli-obk, @lcnr

[rustbot]

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  • 95b3b61

[nnethercote]

Not printing the '_ in this case seems best, because having '_ in type_name_basic::main::Wrap<&'_ ()>::get::Info doesn't seem useful.

[lcnr]

I really dislike that we're printing the path with generic arguments in typenum/during symbol mangling :<

@bors r+ rollup

[bors]

📌 Commit 95b3b61 has been approved by lcnr

It is now in the queue for this repository.

[nnethercote]

I really dislike that we're printing the path with generic arguments in typenum/during symbol mangling :<

What output would you prefer for the new example?

[lcnr]

What output would you prefer for the new example?

I don't have a strong opinion about the output. I would like printing type names (and more importantly symbol mangling), to not support generic parameters. This may allow us to accidentally print/mangle generic symbols which is very :<

We do this only for items defined in impls, and i feel like just printing module_name::{impl#n}::Info would be better. We already do this for closures i think?

use std::any::Any;
use std::any::type_name_of_val;

fn main() {
    struct Wrap<T>(T);
    impl Wrap<&()> {
        fn get(&self) -> impl Any {
            let c_0 = || {
                struct Info;
                Info
            };
            let c_1 = || {
                struct Info;
                Info
            };
            (c_0(), c_1())
        }
    }
    let a = Wrap(&()).get();
    println!("{}", type_name_of_val(&a));
}

I feel like ideally this would print

(main::{impl#0}::get::{{closure#0}}::Info, main::{impl#0}::get::{{closure#1}}::Info)