34 lines
1.1 KiB
Rust
34 lines
1.1 KiB
Rust
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// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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// Test that a covariant region parameter used in a covariant position
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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: &'static mut &'a int
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}
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fn use_<'a>(c: Invariant<'a>) {
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let x = 3;
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// 'b winds up being inferred to 'a, because that is the
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// only way that Invariant<'a> <: Invariant<'b>, and hence
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// we get an error in the borrow checker because &x cannot
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// live that long
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collapse(&x, c); //~ ERROR borrowed value does not live long enough
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fn collapse<'b>(x: &'b int, c: Invariant<'b>) { }
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}
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fn main() { }
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