cc: Keep most recently used resources at the front of resource queue.

cc/base/scoped_ptr_deque.h

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_BASE_SCOPED_PTR_DEQUE_H_
 #define CC_BASE_SCOPED_PTR_DEQUE_H_
 
 #include <algorithm>
 #include <deque>
 
@@ skipping 88 matching lines @@
     data_.insert(position, item.release());
   }
 
   scoped_ptr<T> take(iterator position) {
     DCHECK(position < end());
     scoped_ptr<T> ret(*position);
     data_.erase(position);
     return ret.Pass();
   }
 
+  scoped_ptr<T> rtake(reverse_iterator position) {

[reveman, 2015/11/02 01:47:07]

Instead of adding this, can the user of this class be required to do the
reverse_iterator -> iterator conversion? That seems more consistent with the
underlying std::deque api.

[prashant.n, 2015/11/02 04:07:20]

I think same thing we'll have to do.

iterator it = --position.base();

and call take(it).

IMO, providing rtake will make sense as it can used with reverse iterator. WDYT?

[reveman, 2015/11/02 04:32:59]

as there's no rerase in std::deque I think it's best to also not have an rtake
in this wrapper class. Letting the user of the container take care of this sgtm.

+    DCHECK(position < rend());
+    scoped_ptr<T> ret(*position);
+    data_.erase(--position.base());
+    return ret.Pass();
+  }
+
   void swap(iterator a, iterator b) {
     DCHECK(a < end());
     DCHECK(b < end());
     if (a == end() || b == end() || a == b)
       return;
     typename std::deque<T*>::iterator writable_a = a;
     typename std::deque<T*>::iterator writable_b = b;
     std::swap(*writable_a, *writable_b);
   }
 
   iterator begin() { return static_cast<iterator>(data_.begin()); }
   const_iterator begin() const { return data_.begin(); }
   iterator end() { return static_cast<iterator>(data_.end()); }
   const_iterator end() const { return data_.end(); }
 
   reverse_iterator rbegin() { return data_.rbegin(); }
   const_reverse_iterator rbegin() const { return data_.rbegin(); }
   reverse_iterator rend() { return data_.rend(); }
   const_reverse_iterator rend() const { return data_.rend(); }
 
  private:
   std::deque<T*> data_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedPtrDeque);
 };
 
 }  // namespace cc
 
 #endif  // CC_BASE_SCOPED_PTR_DEQUE_H_