tests/ui/traits/const-traits/issue-100222.rs


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//@ revisions: nn ny yn yy
//@ compile-flags: -Znext-solver
//@ check-pass

#![allow(incomplete_features)]
#![feature(const_trait_impl, associated_type_defaults)]

#[cfg_attr(any(yn, yy), const_trait)]
pub trait Index {
    type Output;
}

#[cfg_attr(any(ny, yy), const_trait)]
pub trait IndexMut
where
    Self: Index,
{
    const C: <Self as Index>::Output;
    type Assoc = <Self as Index>::Output;
    fn foo(&mut self, x: <Self as Index>::Output) -> <Self as Index>::Output;
}

impl Index for () {
    type Output = ();
}

#[cfg(not(any(nn, yn)))]
impl const IndexMut for <() as Index>::Output {
    const C: <Self as Index>::Output = ();
    type Assoc = <Self as Index>::Output;
    fn foo(&mut self, x: <Self as Index>::Output) -> <Self as Index>::Output
    where
        <Self as Index>::Output:,
    {
    }
}

#[cfg(any(nn, yn))]
impl IndexMut for <() as Index>::Output {
    const C: <Self as Index>::Output = ();
    type Assoc = <Self as Index>::Output;
    fn foo(&mut self, x: <Self as Index>::Output) -> <Self as Index>::Output
    where
        <Self as Index>::Output:,
    {
    }
}

const C: <() as Index>::Output = ();

fn main() {}