ee67e14034
In addition to the `Fn*` family of traits, closures now implement `Copy` (and similarly `Clone`) if all of the captures do.
26 lines
763 B
Rust
26 lines
763 B
Rust
// Copyright 2017 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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// Check that closures implement `Copy`.
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fn call<T, F: FnOnce() -> T>(f: F) -> T { f() }
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fn main() {
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let a = 5;
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let hello = || {
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println!("Hello {}", a);
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a
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};
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assert_eq!(5, call(hello.clone()));
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assert_eq!(5, call(hello));
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assert_eq!(5, call(hello));
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}
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