Add methods to Collection.

sdk/lib/core/queue.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.core;
 
 /**
  * A [Queue] is a collection that can be manipulated at both ends. One
  * can iterate over the elements of a queue through [forEach] or with
  * an [Iterator].
@@ skipping 183 matching lines @@
   }
 
   E removeLast() {
     return _sentinel._previous.remove();
   }
 
   E removeFirst() {
     return _sentinel._next.remove();
   }
 
+  void remove(Object o) {
+    DoubleLinkedQueueEntry<E> entry = firstEntry();
+    while (!identical(entry, _sentinel)) {
+      if (entry.element == o) {
+        entry.remove();
+        return;
+      }
+      entry = entry._next;
+    }
+  }
+
+  void removeAll(Iterable elements) {

[floitsch, 2013/01/17 13:36:58]

If Collection provides default implementations, this method should not be
necessary.

[Lasse Reichstein Nielsen, 2013/01/18 11:41:48]

This implementation is not the default implementation.
The default implementation of Collections.removeAll assumes efficient remove, so
successive calls to remove is efficient.
This implementation instead creates an efficient check for being in elements and
uses removeMatching.

I'll add this as Collections.removeAllList.

+    Set set;
+    if (elements is Set) {
+      set = elements;
+    } else {
+      set = elements.toSet();
+    }
+    removeMatching(set.contains);
+  }
+
+  void retainAll(Iterable elements) {

[floitsch, 2013/01/17 13:36:58]

ditto.

[Lasse Reichstein Nielsen, 2013/01/18 11:41:48]

This one is the same as the default, so it can be removed.

+    Set set;
+    if (elements is Set) {
+      set = elements;
+    } else {
+      set = elements.toSet();
+    }
+    retainMatching(set.contains);
+  }
+
+  void removeMatching(bool test(E element)) {
+    DoubleLinkedQueueEntry<E> entry = firstEntry();
+    while (!identical(entry, _sentinel)) {
+      DoubleLinkedQueueEntry<E> next = entry._next;
+      if (test(entry.element)) {
+        entry.remove();
+      }
+      entry = next;
+    }
+  }
+
+  void retainMatching(bool test(E element)) {
+    DoubleLinkedQueueEntry<E> entry = firstEntry();
+    while (!identical(entry, _sentinel)) {
+      DoubleLinkedQueueEntry<E> next = entry._next;
+      if (!test(entry.element)) {
+        entry.remove();
+      }
+      entry = next;
+    }
+  }
+
   E get first {
     return _sentinel._next.element;
   }
 
   E get last {
     return _sentinel._previous.element;
   }
 
   E get single {
     // Note that this also covers the case where the queue is empty.
@@ skipping 58 matching lines @@
       _current = null;
       _sentinel = null;
       return false;
     }
     _current = _currentEntry.element;
     return true;
   }
 
   E get current => _current;
 }