Support PNG and quality control in chrome.tabs.captureVisibleTab().

base/values.h

-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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 66 matching lines @@
   // safe to use the ValueType to determine whether you can cast from
   // Value* to (Implementing Class)*.  Also, a Value object never changes
   // its type after construction.
   ValueType GetType() const { return type_; }
 
   // Returns true if the current object represents a given type.
   bool IsType(ValueType type) const { return type == type_; }
 
   // These methods allow the convenient retrieval of settings.
   // If the current setting object can be converted into the given type,
-  // the value is returned through the "value" parameter and true is returned;
-  // otherwise, false is returned and "value" is unchanged.
+  // the value is returned through the |out_value| parameter and true is
+  // returned;  otherwise, false is returned and |out_value| is unchanged.
   virtual bool GetAsBoolean(bool* out_value) const;
   virtual bool GetAsInteger(int* out_value) const;
   virtual bool GetAsReal(double* out_value) const;
   virtual bool GetAsString(std::string* out_value) const;
   virtual bool GetAsString(std::wstring* out_value) const;
   virtual bool GetAsUTF16(string16* out_value) const;
 
   // This creates a deep copy of the entire Value tree, and returns a pointer
   // to the copy.  The caller gets ownership of the copy, of course.
   virtual Value* DeepCopy() const;
@@ skipping 149 matching lines @@
   void SetStringFromUTF16(const std::wstring& path, const string16& in_value);
 
   // Like Set(), but without special treatment of '.'.  This allows e.g. URLs to
   // be used as paths.
   void SetWithoutPathExpansion(const std::wstring& key, Value* in_value);
 
   // Gets the Value associated with the given path starting from this object.
   // A path has the form "<key>" or "<key>.<key>.[...]", where "." indexes
   // into the next DictionaryValue down.  If the path can be resolved
   // successfully, the value for the last key in the path will be returned
-  // through the "value" parameter, and the function will return true.
-  // Otherwise, it will return false and "value" will be untouched.
+  // through the |out_value| parameter, and the function will return true.
+  // Otherwise, it will return false and |out_value| will be untouched.
   // Note that the dictionary always owns the value that's returned.
   bool Get(const std::wstring& path, Value** out_value) const;
 
   // These are convenience forms of Get().  The value will be retrieved
   // and the return value will be true if the path is valid and the value at
   // the end of the path can be returned in the form specified.
   bool GetBoolean(const std::wstring& path, bool* out_value) const;
   bool GetInteger(const std::wstring& path, int* out_value) const;
   bool GetReal(const std::wstring& path, double* out_value) const;
   bool GetString(const std::string& path, string16* out_value) const;
@@ skipping 91 matching lines @@
   // Returns whether the list is empty.
   bool empty() const { return list_.empty(); }
 
   // Sets the list item at the given index to be the Value specified by
   // the value given.  If the index beyond the current end of the list, null
   // Values will be used to pad out the list.
   // Returns true if successful, or false if the index was negative or
   // the value is a null pointer.
   bool Set(size_t index, Value* in_value);
 
-  // Gets the Value at the given index.  Modifies value (and returns true)
+  // Gets the Value at the given index.  Modifies |out_value| (and returns true)
   // only if the index falls within the current list range.
-  // Note that the list always owns the Value passed out via out_value.
+  // Note that the list always owns the Value passed out via |out_value|.
   bool Get(size_t index, Value** out_value) const;
 
-  // Convenience forms of Get().  Modifies value (and returns true) only if
-  // the index is valid and the Value at that index can be returned in
-  // the specified form.
+  // Convenience forms of Get().  Modifies |out_value| (and returns true) 
+  // only if the index is valid and the Value at that index can be returned 
+  // in the specified form.
   bool GetBoolean(size_t index, bool* out_value) const;
   bool GetInteger(size_t index, int* out_value) const;
   bool GetReal(size_t index, double* out_value) const;
   bool GetString(size_t index, std::string* out_value) const;
   bool GetString(size_t index, std::wstring* out_value) const;
   bool GetStringAsUTF16(size_t index, string16* out_value) const;
   bool GetBinary(size_t index, BinaryValue** out_value) const;
   bool GetDictionary(size_t index, DictionaryValue** out_value) const;
   bool GetList(size_t index, ListValue** out_value) const;
 
@@ skipping 42 matching lines @@
   // 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_code is non-NULL,
   // error_code will be set with the underlying error.
   // If |error_message| is non-null, it will be filled in with a formatted
   // error message including the location of the error if appropriate.
   virtual Value* Deserialize(int* error_code, std::string* error_str) = 0;
 };
 
 #endif  // BASE_VALUES_H_