33 lines
919 B
Rust
33 lines
919 B
Rust
// 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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// Covariant with respect to a region:
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//
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// You can upcast to a *larger region* but not a smaller one.
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struct covariant<'self> {
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f: @fn(x: &'self int) -> int
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}
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fn to_same_lifetime<'r>(bi: covariant<'r>) {
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let bj: covariant<'r> = bi;
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}
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fn to_shorter_lifetime<'r>(bi: covariant<'r>) {
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let bj: covariant<'blk> = bi; //~ ERROR mismatched types
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}
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fn to_longer_lifetime<'r>(bi: covariant<'r>) -> covariant<'static> {
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bi
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}
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fn main() {
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}
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