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base/values.h

 // Copyright (c) 2006-2008 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.
 
 // This file specifies a recursive data storage class called Value
 // intended for storing setting and other persistable data.
 // It includes the ability to specify (recursive) lists and dictionaries, so
 // it's fairly expressive.  However, the API is optimized for the common case,
 // namely storing a hierarchical tree of simple values.  Given a
 // DictionaryValue root, you can easily do things like:
@@ skipping 316 matching lines @@
   bool GetDictionary(size_t index, DictionaryValue** out_value) const;
   bool GetList(size_t index, ListValue** out_value) const;
 
   // Removes the Value with the specified index from this list.
   // If |out_value| is non-NULL, the removed Value AND ITS OWNERSHIP will be
   // passed out via |out_value|.  If |out_value| is NULL, the removed value will
   // be deleted.  This method returns true if |index| is valid; otherwise
   // it will return false and the ListValue object will be unchanged.
   bool Remove(size_t index, Value** out_value);
 
-  // Removes the first instance of |value| found in the list, if any.
-  void Remove(const Value& value);
+  // Removes the first instance of |value| found in the list, if any, returning
+  // the index that it was located at (-1 for not present).
+  int Remove(const Value& value);
 
   // Appends a Value to the end of the list.
   void Append(Value* in_value);
 
+  // Insert a Value at index.
+  // Returns true if successful, or false if the index was out of range.
+  bool Insert(size_t index, Value* in_value);
+
   // Iteration
   typedef ValueVector::iterator iterator;
   typedef ValueVector::const_iterator const_iterator;
 
   ListValue::iterator begin() { return list_.begin(); }
   ListValue::iterator end() { return list_.end(); }
 
   ListValue::const_iterator begin() const { return list_.begin(); }
   ListValue::const_iterator end() const { return list_.end(); }
 
@@ skipping 12 matching lines @@
   virtual bool Serialize(const Value& root) = 0;
 
   // This method deserializes the subclass-specific format into a Value object.
   // If the return value is non-NULL, the caller takes ownership of returned
   // Value. If the return value is NULL, and if error_message is non-NULL,
   // error_message should be filled with a message describing the error.
   virtual Value* Deserialize(std::string* error_message) = 0;
 };
 
 #endif  // BASE_VALUES_H_