mirror of https://github.com/rust-lang/rust
34 lines
590 B
Rust
34 lines
590 B
Rust
//@ run-pass
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#![allow(non_camel_case_types)]
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trait sum {
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fn sum_(self) -> isize;
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}
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// Note: impl on a slice
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impl<'a> sum for &'a [isize] {
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fn sum_(self) -> isize {
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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: &[isize]) -> isize { 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);
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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.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.sum_();
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println!("y=={}", y);
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assert_eq!(y, 6);
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}
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