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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() {}
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