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-rw-r--r--src/test/ui/array-slice-vec/vec-matching-fold.rs46
1 files changed, 46 insertions, 0 deletions
diff --git a/src/test/ui/array-slice-vec/vec-matching-fold.rs b/src/test/ui/array-slice-vec/vec-matching-fold.rs
new file mode 100644
index 000000000..998899271
--- /dev/null
+++ b/src/test/ui/array-slice-vec/vec-matching-fold.rs
@@ -0,0 +1,46 @@
+// run-pass
+
+use std::fmt::Debug;
+
+fn foldl<T, U, F>(values: &[T],
+ initial: U,
+ mut function: F)
+ -> U where
+ U: Clone+Debug, T:Debug,
+ F: FnMut(U, &T) -> U,
+{ match values {
+ &[ref head, ref tail @ ..] =>
+ foldl(tail, function(initial, head), function),
+ &[] => {
+ // FIXME: call guards
+ let res = initial.clone(); res
+ }
+ }
+}
+
+fn foldr<T, U, F>(values: &[T],
+ initial: U,
+ mut function: F)
+ -> U where
+ U: Clone,
+ F: FnMut(&T, U) -> U,
+{
+ match values {
+ &[ref head @ .., ref tail] =>
+ foldr(head, function(tail, initial), function),
+ &[] => {
+ // FIXME: call guards
+ let res = initial.clone(); res
+ }
+ }
+}
+
+pub fn main() {
+ let x = &[1, 2, 3, 4, 5];
+
+ let product = foldl(x, 1, |a, b| a * *b);
+ assert_eq!(product, 120);
+
+ let sum = foldr(x, 0, |a, b| *a + b);
+ assert_eq!(sum, 15);
+}