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-rw-r--r--src/test/ui/run-pass/array-slice-vec/vec-matching-fold.rs56
1 files changed, 56 insertions, 0 deletions
diff --git a/src/test/ui/run-pass/array-slice-vec/vec-matching-fold.rs b/src/test/ui/run-pass/array-slice-vec/vec-matching-fold.rs
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+++ b/src/test/ui/run-pass/array-slice-vec/vec-matching-fold.rs
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+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![feature(slice_patterns)]
+
+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);
+}