| Index: base/linked_list.h
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| diff --git a/base/linked_list.h b/base/linked_list.h
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| deleted file mode 100644
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| index 5b5184f6253854e1f77321157d9a0535d8623fab..0000000000000000000000000000000000000000
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| --- a/base/linked_list.h
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| +++ /dev/null
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| @@ -1,164 +0,0 @@
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| -// Copyright (c) 2009 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 BASE_LINKED_LIST_H_
|
| -#define BASE_LINKED_LIST_H_
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| -
|
| -// Simple LinkedList type. (See the Q&A section to understand how this
|
| -// differs from std::list).
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| -//
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| -// To use, start by declaring the class which will be contained in the linked
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| -// list, as extending LinkNode (this gives it next/previous pointers).
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| -//
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| -// class MyNodeType : public LinkNode<MyNodeType> {
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| -// ...
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| -// };
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| -//
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| -// Next, to keep track of the list's head/tail, use a LinkedList instance:
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| -//
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| -// LinkedList<MyNodeType> list;
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| -//
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| -// To add elements to the list, use any of LinkedList::Append,
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| -// LinkNode::InsertBefore, or LinkNode::InsertAfter:
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| -//
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| -// LinkNode<MyNodeType>* n1 = ...;
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| -// LinkNode<MyNodeType>* n2 = ...;
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| -// LinkNode<MyNodeType>* n3 = ...;
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| -//
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| -// list.Append(n1);
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| -// list.Append(n3);
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| -// n3->InsertBefore(n3);
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| -//
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| -// Lastly, to iterate through the linked list forwards:
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| -//
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| -// for (LinkNode<MyNodeType>* node = list.head();
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| -// node != list.end();
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| -// node = node->next()) {
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| -// MyNodeType* value = node->value();
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| -// ...
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| -// }
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| -//
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| -// Or to iterate the linked list backwards:
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| -//
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| -// for (LinkNode<MyNodeType>* node = list.tail();
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| -// node != list.end();
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| -// node = node->previous()) {
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| -// MyNodeType* value = node->value();
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| -// ...
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| -// }
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| -//
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| -// Questions and Answers:
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| -//
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| -// Q. Should I use std::list or base::LinkedList?
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| -//
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| -// A. The main reason to use base::LinkedList over std::list is
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| -// performance. If you don't care about the performance differences
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| -// then use an STL container, as it makes for better code readability.
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| -//
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| -// Comparing the performance of base::LinkedList<T> to std::list<T*>:
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| -//
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| -// * Erasing an element of type T* from base::LinkedList<T> is
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| -// an O(1) operation. Whereas for std::list<T*> it is O(n).
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| -// That is because with std::list<T*> you must obtain an
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| -// iterator to the T* element before you can call erase(iterator).
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| -//
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| -// * Insertion operations with base::LinkedList<T> never require
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| -// heap allocations.
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| -//
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| -// Q. How does base::LinkedList implementation differ from std::list?
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| -//
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| -// A. Doubly-linked lists are made up of nodes that contain "next" and
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| -// "previous" pointers that reference other nodes in the list.
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| -//
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| -// With base::LinkedList<T>, the type being inserted already reserves
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| -// space for the "next" and "previous" pointers (base::LinkNode<T>*).
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| -// Whereas with std::list<T> the type can be anything, so the implementation
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| -// needs to glue on the "next" and "previous" pointers using
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| -// some internal node type.
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| -
|
| -namespace base {
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| -
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| -template <typename T>
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| -class LinkNode {
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| - public:
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| - LinkNode() : previous_(0), next_(0) {}
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| - LinkNode(LinkNode<T>* previous, LinkNode<T>* next)
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| - : previous_(previous), next_(next) {}
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| -
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| - // Insert |this| into the linked list, before |e|.
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| - void InsertBefore(LinkNode<T>* e) {
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| - this->next_ = e;
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| - this->previous_ = e->previous_;
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| - e->previous_->next_ = this;
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| - e->previous_ = this;
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| - }
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| -
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| - // Insert |this| into the linked list, after |e|.
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| - void InsertAfter(LinkNode<T>* e) {
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| - this->next_ = e->next_;
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| - this->previous_ = e;
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| - e->next_->previous_ = this;
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| - e->next_ = this;
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| - }
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| -
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| - // Remove |this| from the linked list.
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| - void RemoveFromList() {
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| - this->previous_->next_ = this->next_;
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| - this->next_->previous_ = this->previous_;
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| - }
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| -
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| - LinkNode<T>* previous() const {
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| - return previous_;
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| - }
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| -
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| - LinkNode<T>* next() const {
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| - return next_;
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| - }
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| -
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| - // Cast from the node-type to the value type.
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| - const T* value() const {
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| - return static_cast<const T*>(this);
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| - }
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| -
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| - T* value() {
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| - return static_cast<T*>(this);
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| - }
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| -
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| - private:
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| - LinkNode<T>* previous_;
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| - LinkNode<T>* next_;
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| -};
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| -
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| -template <typename T>
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| -class LinkedList {
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| - public:
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| - // The "root" node is self-referential, and forms the basis of a circular
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| - // list (root_.next() will point back to the start of the list,
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| - // and root_->previous() wraps around to the end of the list).
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| - LinkedList() : root_(&root_, &root_) {}
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| -
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| - // Appends |e| to the end of the linked list.
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| - void Append(LinkNode<T>* e) {
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| - e->InsertBefore(&root_);
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| - }
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| -
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| - LinkNode<T>* head() const {
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| - return root_.next();
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| - }
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| -
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| - LinkNode<T>* tail() const {
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| - return root_.previous();
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| - }
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| -
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| - const LinkNode<T>* end() const {
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| - return &root_;
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| - }
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| -
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| - private:
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| - LinkNode<T> root_;
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| -};
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| -
|
| -} // namespace base
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| -
|
| -#endif // BASE_LINKED_LIST_H_
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|
|