/**************************************************************************** ** ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). ** All rights reserved. ** Contact: Nokia Corporation (qt-info@nokia.com) ** ** This file is part of the documentation of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:FDL$ ** No Commercial Usage ** This file contains pre-release code and may not be distributed. ** You may use this file in accordance with the terms and conditions ** contained in the Technology Preview License Agreement accompanying ** this package. ** ** GNU Free Documentation License ** Alternatively, this file may be used under the terms of the GNU Free ** Documentation License version 1.3 as published by the Free Software ** Foundation and appearing in the file included in the packaging of this ** file. ** ** If you have questions regarding the use of this file, please contact ** Nokia at qt-info@nokia.com. ** $QT_END_LICENSE$ ** ****************************************************************************/ /*! \class Q3ValueStack \brief The Q3ValueStack class is a value-based template class that provides a stack. \compat Define a template instance Q3ValueStack\ to create a stack of values that all have the class X. Note that Q3ValueStack does not store pointers to the members of the stack; it holds a copy of every member. That is why these kinds of classes are called "value based"; Q3PtrStack, Q3PtrList, Q3Dict, etc., are "pointer based". A stack is a last in, first out (LIFO) structure. Items are added to the top of the stack with push() and retrieved from the top with pop(). The top() function provides access to the topmost item without removing it. Example: \snippet doc/src/snippets/code/doc_src_q3valuestack.qdoc 0 Q3ValueStack is a specialized Q3ValueList provided for convenience. All of Q3ValueList's functionality also applies to Q3PtrStack, for example the facility to iterate over all elements using Q3ValueStack::Iterator. See Q3ValueListIterator for further details. Some classes cannot be used within a Q3ValueStack, for example everything derived from QObject and thus all classes that implement widgets. Only values can be used in a Q3ValueStack. To qualify as a value, the class must provide \list \i a copy constructor; \i an assignment operator; \i a default constructor, i.e. a constructor that does not take any arguments. \endlist Note that C++ defaults to field-by-field assignment operators and copy constructors if no explicit version is supplied. In many cases this is sufficient. */ /*! \fn Q3ValueStack::Q3ValueStack() Constructs an empty stack. */ /*! \fn Q3ValueStack::~Q3ValueStack() Destroys the stack. References to the values in the stack and all iterators of this stack become invalidated. Because Q3ValueStack is highly tuned for performance, you won't see warnings if you use invalid iterators because it is impossible for an iterator to check whether or not it is valid. */ /*! \fn void Q3ValueStack::push( const T& d ) Adds element, \a d, to the top of the stack. Last in, first out. This function is equivalent to append(). \sa pop(), top() */ /*! \fn T& Q3ValueStack::top() Returns a reference to the top item of the stack or the item referenced by end() if no such item exists. Note that you must not change the value the end() iterator points to. This function is equivalent to last(). \sa pop(), push(), Q3ValueList::fromLast() */ /*! \fn const T& Q3ValueStack::top() const \overload Returns a reference to the top item of the stack or the item referenced by end() if no such item exists. This function is equivalent to last(). \sa pop(), push(), Q3ValueList::fromLast() */ /*! \fn T Q3ValueStack::pop() Removes the top item from the stack and returns it. \sa top() push() */