21 lines
436 B
Rust
21 lines
436 B
Rust
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use core::iter::*;
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#[test]
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fn test_iterator_scan() {
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// test the type inference
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fn add(old: &mut isize, new: &usize) -> Option<f64> {
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*old += *new as isize;
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Some(*old as f64)
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}
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let xs = [0, 1, 2, 3, 4];
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let ys = [0f64, 1.0, 3.0, 6.0, 10.0];
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let it = xs.iter().scan(0, add);
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let mut i = 0;
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for x in it {
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assert_eq!(x, ys[i]);
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i += 1;
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}
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assert_eq!(i, ys.len());
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}
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