From 8641c95221786d13c5e91f1d78c9d0158c376438 Mon Sep 17 00:00:00 2001
From: Brian Anderson <banderson@mozilla.com>
Date: Thu, 29 Mar 2012 22:28:26 -0700
Subject: [PATCH] core: Add str::each_char

---
 src/libcore/str.rs | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/src/libcore/str.rs b/src/libcore/str.rs
index 5d181930b93..2cf3f04fa94 100644
--- a/src/libcore/str.rs
+++ b/src/libcore/str.rs
@@ -55,6 +55,7 @@ export
    all_between, any_between,
    map,
    each,
+   each_char,
    bytes_iter,
    chars_iter,
    split_char_iter,
@@ -635,6 +636,18 @@ fn each(s: str, it: fn(u8) -> bool) {
     }
 }
 
+#[doc = "Iterates over the chars in a string"]
+#[inline(always)]
+fn each_char(s: str, it: fn(char) -> bool) {
+    let mut pos = 0u;
+    let len = len(s);
+    while pos < len {
+        let {ch, next} = char_range_at(s, pos);
+        pos = next;
+        if !it(ch) { break; }
+    }
+}
+
 #[doc = "Iterate over the characters in a string"]
 fn chars_iter(s: str, it: fn(char)) {
     let mut pos = 0u;
@@ -2669,4 +2682,17 @@ mod tests {
             assert to_utf16(from_utf16(u)) == u;
         }
     }
+
+    #[test]
+    fn test_each_char() {
+        let s = "abc";
+        let mut found_b = false;
+        for each_char(s) {|ch|
+            if ch == 'b' {
+                found_b = true;
+                break;
+            }
+        }
+        assert found_b;
+    }
 }