27 lines
571 B
Rust
27 lines
571 B
Rust
//@ run-pass
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#![feature(impl_trait_in_fn_trait_return)]
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use std::fmt::Debug;
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fn f_debug() -> impl Fn() -> impl Debug {
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|| ()
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}
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fn ff_debug() -> impl Fn() -> impl Fn() -> impl Debug {
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|| f_debug()
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}
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fn multi() -> impl Fn() -> (impl Debug + Send) {
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|| ()
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}
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fn main() {
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// Check that `ff_debug` is `() -> (() -> Debug)` and not `(() -> ()) -> Debug`
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let debug = ff_debug()()();
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assert_eq!(format!("{:?}", debug), "()");
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let x = multi()();
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assert_eq!(format!("{:?}", x), "()");
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fn assert_send(_: &impl Send) {}
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assert_send(&x);
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}
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