mirror of https://github.com/rust-lang/rust
28 lines
725 B
Rust
28 lines
725 B
Rust
//@ run-pass
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#![allow(dead_code)]
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#![allow(unused_variables)]
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// Test that a type which is contravariant with respect to its region
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// parameter compiles successfully when used in a contravariant way.
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//
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// Note: see ui/variance/variance-regions-*.rs for the tests that check that the
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// variance inference works in the first place.
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//@ pretty-expanded FIXME #23616
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struct Contravariant<'a> {
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f: &'a isize
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}
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fn use_<'a>(c: Contravariant<'a>) {
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let x = 3;
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// 'b winds up being inferred to this call.
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// Contravariant<'a> <: Contravariant<'call> is true
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// if 'call <= 'a, which is true, so no error.
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collapse(&x, c);
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fn collapse<'b>(x: &'b isize, c: Contravariant<'b>) { }
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}
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pub fn main() {}
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