tqt3/doc/qvaluestack.doc

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** QValueStack class documentation
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/*****************************************************************************
  QValueStack documentation
 *****************************************************************************/

/*!
    \class QValueStack ntqvaluestack.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\<X\> to create a stack of
    values that all have the class X. QValueStack is part of the \link
    ntqtl.html TQt 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<int> 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<T>::Iterator. See QValueListIterator for further
    details.

    Some classes cannot be used within a QValueStack, for example
    everything derived from TQObject 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()
*/