rust/tests/ui/impl-trait/impl-fn-rpit-opaque-107883.rs

38 lines
648 B
Rust

//@ check-pass
// Regression test for <https;//github.com/rust-lang/rust/issues/107883>
#![feature(impl_trait_in_fn_trait_return)]
#![feature(unboxed_closures)] // only for `h`
use std::fmt::Debug;
fn f<T>() -> impl Fn(T) -> impl Debug {
|_x| 15
}
fn g<T>() -> impl MyFn<(T,), Out = impl Debug> {
|_x| 15
}
trait MyFn<T> {
type Out;
}
impl<T, U, F: Fn(T) -> U> MyFn<(T,)> for F {
type Out = U;
}
fn h<T>() -> impl Fn<(T,), Output = impl Debug> {
|_x| 15
}
fn f_<T>() -> impl Fn(T) -> impl Debug {
std::convert::identity(|_x| 15)
}
fn f__<T>() -> impl Fn(T) -> impl Debug {
let r = |_x| 15;
r
}
fn main() {}