41 lines
1.0 KiB
Rust
41 lines
1.0 KiB
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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trait sum {
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fn sum_(self) -> int;
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}
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// Note: impl on a slice
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impl<'a> sum for &'a [int] {
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fn sum_(self) -> int {
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self.iter().fold(0, |a, &b| a + b)
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}
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}
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fn call_sum(x: &[int]) -> int { x.sum_() }
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pub fn main() {
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let x = vec!(1, 2, 3);
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let y = call_sum(x.as_slice());
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println!("y=={}", y);
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assert_eq!(y, 6);
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let x = vec!(1, 2, 3);
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let y = x.as_slice().sum_();
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println!("y=={}", y);
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assert_eq!(y, 6);
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let x = vec!(1, 2, 3);
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let y = x.as_slice().sum_();
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println!("y=={}", y);
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assert_eq!(y, 6);
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}
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