/**************************************************************************** ** ** QValueStack class documentation ** ** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved. ** ** This file is part of the Qt GUI Toolkit. ** ** This file may be used under the terms of the GNU General ** Public License versions 2.0 or 3.0 as published by the Free ** Software Foundation and appearing in the files LICENSE.GPL2 ** and LICENSE.GPL3 included in the packaging of this file. ** Alternatively you may (at your option) use any later version ** of the GNU General Public License if such license has been ** publicly approved by Trolltech ASA (or its successors, if any) ** and the KDE Free Qt Foundation. ** ** Please review the following information to ensure GNU General ** Public Licensing requirements will be met: ** http://trolltech.com/products/qt/licenses/licensing/opensource/. ** If you are unsure which license is appropriate for your use, please ** review the following information: ** http://trolltech.com/products/qt/licenses/licensing/licensingoverview ** or contact the sales department at sales@trolltech.com. ** ** This file may be used under the terms of the Q Public License as ** defined by Trolltech ASA and appearing in the file LICENSE.QPL ** included in the packaging of this file. Licensees holding valid Qt ** Commercial licenses may use this file in accordance with the Qt ** Commercial License Agreement provided with the Software. ** ** This file is provided "AS IS" with NO WARRANTY OF ANY KIND, ** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted ** herein. ** **********************************************************************/ /***************************************************************************** QValueStack documentation *****************************************************************************/ /*! \class QValueStack qvaluestack.h \brief The QValueStack class is a value-based template class that provides a stack. \ingroup qtl \ingroup tools \ingroup shared \mainclass \reentrant Define a template instance QValueStack\ to create a stack of values that all have the class X. QValueStack is part of the \link qtl.html Qt Template Library\endlink. Note that QValueStack 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"; QPtrStack, QPtrList, QDict, 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: \code QValueStack stack; stack.push( 1 ); stack.push( 2 ); stack.push( 3 ); while ( ! stack.isEmpty() ) cout << "Item: " << stack.pop() << endl; // Output: // Item: 3 // Item: 2 // Item: 1 \endcode QValueStack is a specialized QValueList provided for convenience. All of QValueList's functionality also applies to QPtrStack, for example the facility to iterate over all elements using QValueStack::Iterator. See QValueListIterator for further details. Some classes cannot be used within a QValueStack, for example everything derived from QObject and thus all classes that implement widgets. Only values can be used in a QValueStack. 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 QValueStack::QValueStack() Constructs an empty stack. */ /*! \fn QValueStack::~QValueStack() Destroys the stack. References to the values in the stack and all iterators of this stack become invalidated. Because QValueStack 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 QValueStack::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& QValueStack::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(), QValueList::fromLast() */ /*! \fn const T& QValueStack::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(), QValueList::fromLast() */ /*! \fn T QValueStack::pop() Removes the top item from the stack and returns it. \sa top() push() */