30 lines
1.0 KiB
Rust
30 lines
1.0 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 type which is covariant with respect to its region
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// parameter is successful when used in a covariant way.
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//
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// Note: see compile-fail/variance-regions-*.rs for the tests that
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// check that the variance inference works in the first place.
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// This is covariant with respect to 'a, meaning that
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// Covariant<'foo> <: Covariant<'static> because
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// 'foo <= 'static
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struct Covariant<'a> {
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f: extern "Rust" fn(&'a int)
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}
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fn use_<'a>(c: Covariant<'a>) {
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// OK Because Covariant<'a> <: Covariant<'static> iff 'a <= 'static
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let _: Covariant<'static> = c;
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}
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fn main() {}
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