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