mirror of https://github.com/rust-lang/rust
25 lines
736 B
Rust
25 lines
736 B
Rust
// Test that an invariant region parameter used in a contravariant way
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// yields an error.
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//
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// Note: see 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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struct Invariant<'a> {
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f: &'a mut &'a isize
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}
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fn use_<'short,'long>(c: Invariant<'long>,
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s: &'short isize,
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l: &'long isize,
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_where:Option<&'short &'long ()>) {
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// Test whether Invariant<'long> <: Invariant<'short>. Since
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// 'short <= 'long, this would be true if the Invariant type were
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// contravariant with respect to its parameter 'a.
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let _: Invariant<'short> = c;
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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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