---

yaml
---
r: 142446
b: refs/heads/try2
c: 40ce0b7
h: refs/heads/master
v: v3

Author: blake2-ppc

[refs]

@@ -5,7 +5,7 @@ refs/heads/snap-stage3: 78a7676898d9f80ab540c6df5d4c9ce35bb50463
 refs/heads/try: 519addf6277dbafccbb4159db4b710c37eaa2ec5
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
-refs/heads/try2: 81933edf92afda59ea41ec3692ab43759285b731
+refs/heads/try2: 40ce0b7d76fe39c58e4bdf119af33c4d24950077
 refs/heads/dist-snap: ba4081a5a8573875fed17545846f6f6902c8ba8d
 refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596
 refs/tags/release-0.3: b5f0d0f648d9a6153664837026ba1be43d3e2503

branches/try2/src/libextra/deque.rs

@@ -11,7 +11,6 @@
 //! A double-ended queue implemented as a circular buffer
 
 use std::uint;
-use std::util::replace;
 use std::vec;
 use std::cast::transmute;
 
@@ -103,28 +102,28 @@ impl<T> Deque<T> {
 
     /// Prepend an element to the deque
     pub fn add_front(&mut self, t: T) {
-        let oldlo = self.lo;
+        if self.nelts == self.elts.len() {
+            grow(self.nelts, self.lo, &mut self.elts);
+            self.hi = self.lo + self.nelts;
+        }
         if self.lo == 0u {
             self.lo = self.elts.len() - 1u;
         } else { self.lo -= 1u; }
-        if self.nelts == self.elts.len() {
-            self.elts = grow(self.nelts, oldlo, self.elts);
-            self.lo = self.elts.len() - 1u;
-            self.hi = self.nelts;
-        }
         self.elts[self.lo] = Some(t);
         self.nelts += 1u;
     }
 
     /// Append an element to the deque
     pub fn add_back(&mut self, t: T) {
         if self.lo == self.hi && self.nelts != 0u {
-            self.elts = grow(self.nelts, self.lo, self.elts);
-            self.lo = 0u;
-            self.hi = self.nelts;
+            grow(self.nelts, self.lo, &mut self.elts);
+            self.hi = self.lo + self.nelts;
         }
         self.elts[self.hi] = Some(t);
-        self.hi = (self.hi + 1u) % self.elts.len();
+        self.hi += 1;
+        if self.hi == self.elts.len() {
+            self.hi = 0;
+        }
         self.nelts += 1u;
     }
 
@@ -235,15 +234,19 @@ iterator!{impl DequeMutRevIterator -> &'self mut T, -1}
 
 /// Grow is only called on full elts, so nelts is also len(elts), unlike
 /// elsewhere.
-fn grow<T>(nelts: uint, lo: uint, elts: &mut [Option<T>]) -> ~[Option<T>] {
+fn grow<T>(nelts: uint, lo: uint, elts: &mut ~[Option<T>]) {
     assert_eq!(nelts, elts.len());
-    let mut rv = ~[];
+    let newlen = elts.capacity() * 2;
+    elts.reserve(newlen);
 
-    do rv.grow_fn(nelts + 1) |i| {
-        replace(&mut elts[(lo + i) % nelts], None)
+    /* fill with None */
+    for uint::range(elts.len(), elts.capacity()) |_| {
+        elts.push(None);
+    }
+    /* move the former wraparound to the new half */
+    for uint::range(0, lo) |i| {
+        elts.swap(i, nelts + i);
     }
-
-    rv
 }
 
 fn get<'r, T>(elts: &'r [Option<T>], i: uint) -> &'r T {