28 lines
623 B
Rust
28 lines
623 B
Rust
#[doc = "Operations on tuples"];
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#[doc = "Return the first element of a pair"]
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pure fn first<T:copy, U:copy>(pair: (T, U)) -> T {
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let (t, _) = pair;
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ret t;
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}
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#[doc = "Return the second element of a pair"]
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pure fn second<T:copy, U:copy>(pair: (T, U)) -> U {
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let (_, u) = pair;
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ret u;
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}
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#[doc = "Return the results of swapping the two elements of a pair"]
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pure fn swap<T:copy, U:copy>(pair: (T, U)) -> (U, T) {
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let (t, u) = pair;
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ret (u, t);
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}
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#[test]
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fn test_tuple() {
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assert first((948, 4039.48)) == 948;
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assert second((34.5, "foo")) == "foo";
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assert swap(('a', 2)) == (2, 'a');
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}
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