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			15 lines
		
	
	
		
			395 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			15 lines
		
	
	
		
			395 B
		
	
	
	
		
			Rust
		
	
	
	
	
	
| // run-pass
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| 
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| #![allow(warnings)]
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| 
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| // Here the type of `c` is `Option<?T>`, where `?T` is unconstrained.
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| // Because there is data-flow from the `{ return; }` block, which
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| // diverges and hence has type `!`, into `c`, we will default `?T` to
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| // `!`, and hence this code compiles rather than failing and requiring
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| // a type annotation.
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| 
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| fn main() {
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|     let c = Some({ return; });
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|     c.unwrap();
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| }
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