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			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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| 
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| fn f_debug() -> impl Fn() -> impl Debug {
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|     || ()
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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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| 
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| fn multi() -> impl Fn() -> (impl Debug + Send) {
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|     || ()
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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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| 
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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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