mirror of https://github.com/rust-lang/rust
28 lines
645 B
Rust
28 lines
645 B
Rust
#![allow(dead_code)]
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// Test that even when `T` is only used in covariant position, it
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// is treated as invariant.
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trait Get<T> : 'static {
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fn get(&self) -> T;
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}
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fn get_min_from_max<'min, 'max>(v: Box<dyn Get<&'max i32>>)
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-> Box<dyn Get<&'min i32>>
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where 'max : 'min
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{
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// Previously OK, now an error as traits are invariant.
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v
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//~^ ERROR lifetime may not live long enough
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}
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fn get_max_from_min<'min, 'max>(v: Box<dyn Get<&'min i32>>)
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-> Box<dyn Get<&'max i32>>
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where 'max : 'min
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{
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v
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//~^ ERROR lifetime may not live long enough
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}
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fn main() { }
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