libstd => libcore

1 files changed, 28 insertions, 0 deletions

diff --git a/src/libcore/tuple.rs b/src/libcore/tuple.rs
new file mode 100644
index 00000000000..9d24f428d42
--- /dev/null
+++ b/src/libcore/tuple.rs
@@ -0,0 +1,28 @@
+/*
+Module: tuple
+*/
+
+// FIXME #1546: Would rather write fst<T, U>(+pair: (T, U)) -> T
+fn first<T:copy, U:copy>(pair: (T, U)) -> T {
+    let (t, _) = pair;
+    ret t;
+}
+
+fn second<T:copy, U:copy>(pair: (T, U)) -> U {
+    let (_, u) = pair;
+    ret u;
+}
+
+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');
+}
+