src/test/ui/impl-trait/region-escape-via-bound-contravariant-closure.rs


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// In contrast to `region-escape-via-bound-invariant`, in this case we
// *can* return a value of type `&'x u32`, even though `'x` does not
// appear in the bounds. This is because `&` is contravariant, and so
// we are *actually* returning a `&'y u32`.
//
// See https://github.com/rust-lang/rust/issues/46541 for more details.

// run-pass

#![allow(dead_code)]

fn foo<'x, 'y>(x: &'x u32) -> impl Fn() -> &'y u32
where 'x: 'y
{
    move || x
}

fn main() { }