34 lines
846 B
Rust
34 lines
846 B
Rust
// Copyright 2014 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 by-ref capture of environment in unboxed closure types
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fn call_fn<F: Fn()>(f: F) {
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f()
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}
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fn call_fn_mut<F: FnMut()>(mut f: F) {
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f()
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}
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fn call_fn_once<F: FnOnce()>(f: F) {
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f()
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}
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fn main() {
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let mut x = 0_usize;
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let y = 2_usize;
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call_fn(|| assert_eq!(x, 0));
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call_fn_mut(|| x += y);
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call_fn_once(|| x += y);
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assert_eq!(x, y * 2);
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}
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