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QValueList(3qt) 								  QValueList(3qt)

NAME
       QValueList - Value-based template class that provides lists

SYNOPSIS
       All the functions in this class are reentrant when Qt is built with thread support.</p>

       #include <qvaluelist.h>

       Inherited by QCanvasItemList, QStringList, and QValueStack.

   Public Members
       typedef QValueListIterator<T> iterator
       typedef QValueListConstIterator<T> const_iterator
       typedef T value_type
       typedef value_type * pointer
       typedef const value_type * const_pointer
       typedef value_type & reference
       typedef const value_type & const_reference
       typedef size_t size_type
       QValueList ()
       QValueList ( const QValueList<T> & l )
       QValueList ( const std::list<T> & l )
       ~QValueList ()
       QValueList<T> & operator= ( const QValueList<T> & l )
       QValueList<T> & operator= ( const std::list<T> & l )
       bool operator== ( const std::list<T> & l ) const
       bool operator== ( const QValueList<T> & l ) const
       bool operator!= ( const QValueList<T> & l ) const
       iterator begin ()
       const_iterator begin () const
       const_iterator constBegin () const
       iterator end ()
       const_iterator end () const
       const_iterator constEnd () const
       iterator insert ( iterator it, const T & x )
       uint remove ( const T & x )
       void clear ()
       QValueList<T> & operator<< ( const T & x )
       size_type size () const
       bool empty () const
       void push_front ( const T & x )
       void push_back ( const T & x )
       iterator erase ( iterator it )
       iterator erase ( iterator first, iterator last )
       reference front ()
       const_reference front () const
       reference back ()
       const_reference back () const
       void pop_front ()
       void pop_back ()
       void insert ( iterator pos, size_type n, const T & x )
       QValueList<T> operator+ ( const QValueList<T> & l ) const
       QValueList<T> & operator+= ( const QValueList<T> & l )
       iterator fromLast ()
       const_iterator fromLast () const
       bool isEmpty () const
       iterator append ( const T & x )
       iterator prepend ( const T & x )
       iterator remove ( iterator it )
       T & first ()
       const T & first () const
       T & last ()
       const T & last () const
       T & operator[] ( size_type i )
       const T & operator[] ( size_type i ) const
       iterator at ( size_type i )
       const_iterator at ( size_type i ) const
       iterator find ( const T & x )
       const_iterator find ( const T & x ) const
       iterator find ( iterator it, const T & x )
       const_iterator find ( const_iterator it, const T & x ) const
       int findIndex ( const T & x ) const
       size_type contains ( const T & x ) const
       size_type count () const
       QValueList<T> & operator+= ( const T & x )
       typedef QValueListIterator<T> Iterator
       typedef QValueListConstIterator<T> ConstIterator

RELATED FUNCTION DOCUMENTATION
       QDataStream & operator>> ( QDataStream & s, QValueList<T> & l )
       QDataStream & operator<< ( QDataStream & s, const QValueList<T> & l )

DESCRIPTION
       The QValueList class is a value-based template class that provides lists.

       QValueList is a Qt implementation of an STL-like list container. It can be used in your
       application if the standard list is not available for your target platform(s). QValueList
       is part of the Qt Template Library.

       QValueList<T> defines a template instance to create a list of values that all have the
       class T. Note that QValueList does not store pointers to the members of the list; it holds
       a copy of every member. This is why these kinds of classes are called "value based";
       QPtrList and QDict are "pointer based".

       QValueList contains and manages a collection of objects of type T and provides iterators
       that allow the contained objects to be addressed. QValueList owns the contained items. For
       more relaxed ownership semantics, see QPtrCollection and friends which are pointer-based
       containers.

       Some classes cannot be used within a QValueList, for example, all classes derived from
       QObject and thus all classes that implement widgets. Only values can be used in a
       QValueList. To qualify as a value the class must provide:

       a copy constructor;

       an assignment operator;

       a default constructor, i.e. a constructor that does not take any arguments.

       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.

       In addition, some compilers (e.g. Sun CC) might require that the class provides an
       equality operator (operator==()).

       QValueList's function naming is consistent with the other Qt classes (e.g. count(),
       isEmpty()). QValueList also provides extra functions for compatibility with STL
       algorithms, such as size() and empty(). Programmers already familiar with the STL list may
       prefer to use the STL-compatible functions.

       Example:

	   class Employee
	   {
	   public:
	       Employee(): sn(0) {}
	       Employee( const QString& forename, const QString& surname, int salary )
		   : fn(forename), sn(surname), sal(salary)
	       {}
	       QString forename() const { return fn; }
	       QString surname() const { return sn; }
	       int salary() const { return sal; }
	       void setSalary( int salary ) { sal = salary; }
	   private:
	       QString fn;
	       QString sn;
	       int sal;
	   };
	   typedef QValueList<Employee> EmployeeList;
	   EmployeeList list;
	   list.append( Employee("John", "Doe", 50000) );
	   list.append( Employee("Jane", "Williams", 80000) );
	   list.append( Employee("Tom", "Jones", 60000) );
	   Employee mary( "Mary", "Hawthorne", 90000 );
	   list.append( mary );
	   mary.setSalary( 100000 );
	   EmployeeList::iterator it;
	   for ( it = list.begin(); it != list.end(); ++it )
	       cout << (*it).surname().latin1() << ", " <<
		       (*it).forename().latin1() << " earns " <<
		       (*it).salary() << endl;
	   // Output:
	   // Doe, John earns 50000
	   // Williams, Jane earns 80000
	   // Hawthorne, Mary earns 90000
	   // Jones, Tom earns 60000

       Notice that the latest changes to Mary's salary did not affect the value in the list
       because the list created a copy of Mary's entry.

       There are several ways to find items in the list. The begin() and end() functions return
       iterators to the beginning and end of the list. The advantage of getting an iterator is
       that you can move forward or backward from this position by incrementing/decrementing the
       iterator. The iterator returned by end() points to the item which is one past the last
       item in the container. The past-the-end iterator is still associated with the list it
       belongs to, however it is not dereferenceable; operator*() will not return a well-defined
       value. If the list is empty(), the iterator returned by begin() will equal the iterator
       returned by end().

       Another way to find an item in the list is by using the qFind() algorithm. For example:

	   QValueList<int> list;
	   ...
	   QValueList<int>::iterator it = qFind( list.begin(), list.end(), 3 );
	   if ( it != list.end() )
	       // it points to the found item

       It is safe to have multiple iterators a the list at the same time. If some member of the
       list is removed, only iterators pointing to the removed member become invalid. Inserting
       into the list does not invalidate any iterator. For convenience, the function last()
       returns a reference to the last item in the list, and first() returns a reference to the
       the first item. If the list is empty(), both last() and first() have undefined behavior
       (your application will crash or do unpredictable things). Use last() and first() with
       caution, for example:

	   QValueList<int> list;
	   list.append( 1 );
	   list.append( 2 );
	   list.append( 3 );
	   ...
	   if ( !list.empty() ) {
	       // OK, modify the first item
	       int& i = list.first();
	       i = 18;
	   }
	   ...
	   QValueList<double> dlist;
	   double d = dlist.last(); // undefined

       Because QValueList is value-based there is no need to be careful about deleting items in
       the list. The list holds its own copies and will free them if the corresponding member or
       the list itself is deleted. You can force the list to free all of its items with clear().

       QValueList is shared implicitly, which means it can be copied in constant time, i.e. O(1).
       If multiple QValueList instances share the same data and one needs to modify its contents,
       this modifying instance makes a copy and modifies its private copy; therefore it does not
       affect the other instances; this takes O(n) time. This is often called "copy on write". If
       a QValueList is being used in a multi-threaded program, you must protect all access to the
       list. See QMutex.

       There are several ways to insert items into the list. The prepend() and append() functions
       insert items at the beginning and the end of the list respectively. The insert() function
       comes in several flavors and can be used to add one or more items at specific positions
       within the list.

       Items can also be removed from the list in several ways. There are several variants of the
       remove() function, which removes a specific item from the list. The remove() function will
       find and remove items according to a specific item value.

       Lists can also be sorted using the Qt Template Library. For example with qHeapSort():

       Example:

	   QValueList<int> list;
	   list.append( 5 );
	   list.append( 8 );
	   list.append( 3 );
	   list.append( 4 );
	   qHeapSort( list );

       See also QValueListIterator, Qt Template Library Classes, Implicitly and Explicitly Shared
       Classes, and Non-GUI Classes.

   Member Type Documentation
QValueList::ConstIterator
       This iterator is an instantiation of QValueListConstIterator for the same type as this
       QValueList. In other words, if you instantiate QValueList<int>, ConstIterator is a
       QValueListConstIterator<int>. Several member function use it, such as QValueList::begin(),
       which returns an iterator pointing to the first item in the list.

       Functionally, this is almost the same as Iterator. The only difference is you cannot use
       ConstIterator for non-const operations, and that the compiler can often generate better
       code if you use ConstIterator.

       See also QValueListIterator and Iterator.

QValueList::Iterator
       This iterator is an instantiation of QValueListIterator for the same type as this
       QValueList. In other words, if you instantiate QValueList<int>, Iterator is a
       QValueListIterator<int>. Several member function use it, such as QValueList::begin(),
       which returns an iterator pointing to the first item in the list.

       Functionally, this is almost the same as ConstIterator. The only difference is that you
       cannot use ConstIterator for non-const operations, and that the compiler can often
       generate better code if you use ConstIterator.

       See also QValueListIterator and ConstIterator.

QValueList::const_iterator
       The list's const iterator type, QValueListConstIterator.

QValueList::const_pointer
       The const pointer to T type.

QValueList::const_reference
       The const reference to T type.

QValueList::iterator
       The list's iterator type, QValueListIterator.

QValueList::pointer
       The pointer to T type.

QValueList::reference
       The reference to T type.

QValueList::size_type
       An unsigned integral type, used to represent various sizes.

QValueList::value_type
       The type of the object stored in the list, T.

MEMBER FUNCTION DOCUMENTATION
QValueList::QValueList ()
       Constructs an empty list.

QValueList::QValueList ( const QValueList<T> & l )
       Constructs a copy of l.

       This operation takes O(1) time because QValueList is implicitly shared.

       The first modification to a list will take O(n) time.

QValueList::QValueList ( const std::list<T> & l )
       Contructs a copy of l.

       This constructor is provided for compatibility with STL containers.

QValueList::~QValueList ()
       Destroys the list. References to the values in the list and all iterators of this list
       become invalidated. Note that it is impossible for an iterator to check whether or not it
       is valid: QValueList is highly tuned for performance, not for error checking.

iterator QValueList::append ( const T & x )
       Inserts x at the end of the list.

       See also insert() and prepend().

       Examples:

const_iterator QValueList::at ( size_type i ) const
       Returns an iterator pointing to the item at position i in the list, or an undefined value
       if the index is out of range.

       Warning: This function uses a linear search and can be extremely slow for large lists.
       QValueList is not optimized for random item access. If you need random access use a
       different container, such as QValueVector.

iterator QValueList::at ( size_type i )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns an iterator pointing to the item at position i in the list, or an undefined value
       if the index is out of range.

reference QValueList::back ()
       Returns a reference to the last item. If the list contains no last item (i.e. empty()
       returns TRUE), the return value is undefined.

       This function is provided for STL compatibility. It is equivalent to last().

       See also front().

const_reference QValueList::back () const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

const_iterator QValueList::begin () const
       Returns an iterator pointing to the first item in the list. This iterator equals end() if
       the list is empty.

       See also first(), end(), and constBegin().

       Examples:

iterator QValueList::begin ()
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns an iterator pointing to the first item in the list. This iterator equals end() if
       the list is empty.

       See also first() and end().

void QValueList::clear ()
       Removes all items from the list.

       See also remove().

const_iterator QValueList::constBegin () const
       Returns an iterator pointing to the first item in the list. This iterator equals
       constEnd() if the list is empty.

       See also begin().

const_iterator QValueList::constEnd () const
       Returns an iterator pointing past the last item in the list. This iterator equals
       constBegin() if the list is empty.

       See also end().

size_type QValueList::contains ( const T & x ) const
       Returns the number of occurrences of the value x in the list.

size_type QValueList::count () const
       Returns the number of items in the list.

       See also isEmpty().

       Examples:

bool QValueList::empty () const
       Returns TRUE if the list contains no items; otherwise returns FALSE.

       See also size().

iterator QValueList::end ()
       Returns an iterator pointing past the last item in the list. This iterator equals begin()
       if the list is empty.

       See also last(), begin(), and constEnd().

       Examples:

const_iterator QValueList::end () const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns an iterator pointing past the last item in the list. This iterator equals begin()
       if the list is empty.

       See also last() and begin().

iterator QValueList::erase ( iterator it )
       Removes the item pointed to by it from the list. No iterators other than it or other
       iterators pointing at the same item as it are invalidated. Returns an iterator to the next
       item after it, or end() if there is no such item.

       This function is provided for STL compatibility. It is equivalent to remove().

iterator QValueList::erase ( iterator first, iterator last )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Deletes all items from first to last (not including last). No iterators are invalidated,
       except those pointing to the removed items themselves. Returns last.

iterator QValueList::find ( const T & x )
       Returns an iterator pointing to the first occurrence of x in the list.

       Returns end() is no item matched.

const_iterator QValueList::find ( const T & x ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns an iterator pointing to the first occurrence of x in the list.

       Returns end() if no item matched.

iterator QValueList::find ( iterator it, const T & x )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Finds the first occurrence of x in the list starting at the position given by it.

       Returns end() if no item matched.

const_iterator QValueList::find ( const_iterator it, const T & x ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Finds the first occurrence of x in the list starting at the position given by it.

       Returns end() if no item matched.

int QValueList::findIndex ( const T & x ) const
       Returns the index of the first occurrence of the value x. Returns -1 if no item matched.

T &; QValueList::first ()
       Returns a reference to the first item. If the list contains no first item (i.e. isEmpty()
       returns TRUE), the return value is undefined.

       See also last().

       Example: network/mail/smtp.cpp.

const T &; QValueList::first () const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

const_iterator QValueList::fromLast () const
       Returns an iterator to the last item in the list, or end() if there is no last item.

       Use the end() function instead. For example:

	   QValueList<int> l;
	   ...
	   QValueList<int>::iterator it = l.end();
	   --it;
	   if ( it != end() )
	       // ...

iterator QValueList::fromLast ()
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns an iterator to the last item in the list, or end() if there is no last item.

       Use the end() function instead. For example:

	   QValueList<int> l;
	   ...
	   QValueList<int>::iterator it = l.end();
	   --it;
	   if ( it != end() )
	       // ...

reference QValueList::front ()
       Returns a reference to the first item. If the list contains no first item (i.e. empty()
       returns TRUE), the return value is undefined.

       This function is provided for STL compatibility. It is equivalent to first().

       See also back().

const_reference QValueList::front () const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

iterator QValueList::insert ( iterator it, const T & x )
       Inserts the value x in front of the item pointed to by the iterator, it.

       Returns an iterator pointing at the inserted item.

       See also append() and prepend().

       Example: themes/themes.cpp.

void QValueList::insert ( iterator pos, size_type n, const T & x )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Inserts n copies of x before position pos.

bool QValueList::isEmpty () const
       Returns TRUE if the list contains no items; otherwise returns FALSE.

       See also count().

       Examples:

T &; QValueList::last ()
       Returns a reference to the last item. If the list contains no last item (i.e. empty()
       returns TRUE), the return value is undefined.

const T &; QValueList::last () const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

bool QValueList::operator!= ( const QValueList<T> & l ) const
       Compares both lists.

       Returns TRUE if this list and l are unequal; otherwise returns FALSE.

QValueList<;T> QValueList::operator+ ( const QValueList<T> & l ) const
       Creates a new list and fills it with the items of this list. Then the items of l are
       appended. Returns the new list.

QValueList<;T> & QValueList::operator+= ( const QValueList<T> & l )
       Appends the items of l to this list. Returns a reference to this list.

QValueList<;T> & QValueList::operator+= ( const T & x )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Appends the value x to the list. Returns a reference to the list.

QValueList<;T> & QValueList::operator<< ( const T & x )
       Adds the value x to the end of the list.

       Returns a reference to the list.

QValueList<;T> & QValueList::operator= ( const QValueList<T> & l )
       Assigns l to this list and returns a reference to this list.

       All iterators of the current list become invalidated by this operation. The cost of such
       an assignment is O(1) since QValueList is implicitly shared.

QValueList<;T> & QValueList::operator= ( const std::list<T> & l )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Assigns the contents of l to the list.

       All iterators of the current list become invalidated by this operation.

bool QValueList::operator== ( const QValueList<T> & l ) const
       Compares both lists.

       Returns TRUE if this list and l are equal; otherwise returns FALSE.

bool QValueList::operator== ( const std::list<T> & l ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns TRUE if this list and l are equal; otherwise returns FALSE.

       This operator is provided for compatibility with STL containers.

const T &; QValueList::operator[] ( size_type i ) const
       Returns a const reference to the item with index i in the list. It is up to you to check
       whether this item really exists. You can do that easily with the count() function. However
       this operator does not check whether i is in range and will deliver undefined results if
       it does not exist.

       Warning: This function uses a linear search and can be extremely slow for large lists.
       QValueList is not optimized for random item access. If you need random access use a
       different container, such as QValueVector.

T &; QValueList::operator[] ( size_type i )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns a non-const reference to the item with index i.

void QValueList::pop_back ()
       Removes the last item. If there is no last item, this operation is undefined.

       This function is provided for STL compatibility.

void QValueList::pop_front ()
       Removes the first item. If there is no first item, this operation is undefined.

       This function is provided for STL compatibility.

iterator QValueList::prepend ( const T & x )
       Inserts x at the beginning of the list.

       See also insert() and append().

void QValueList::push_back ( const T & x )
       Inserts x at the end of the list.

       This function is provided for STL compatibility. It is equivalent to append().

void QValueList::push_front ( const T & x )
       Inserts x at the beginning of the list.

       This function is provided for STL compatibility. It is equivalent to prepend().

       Example: toplevel/options.ui.h.

iterator QValueList::remove ( iterator it )
       Removes the item pointed to by it from the list. No iterators other than it or other
       iterators pointing at the same item as it are invalidated. Returns an iterator to the next
       item after it, or end() if there is no such item.

       See also clear().

uint QValueList::remove ( const T & x )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Removes all items that have value x and returns the number of removed items.

size_type QValueList::size () const
       Returns the number of items in the list.

       This function is provided for STL compatibility. It is equivalent to count().

       See also empty().

RELATED FUNCTION DOCUMENTATION
QDataStream &; operator<< ( QDataStream & s, const QValueList<T> & l )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Writes a list, l, to the stream s. The type T stored in the list must implement the
       streaming operator.

QDataStream &; operator>> ( QDataStream & s, QValueList<T> & l )
       Reads a list, l, from the stream s. The type T stored in the list must implement the
       streaming operator.

SEE ALSO
       http://doc.trolltech.com/qvaluelist.html http://www.trolltech.com/faq/tech.html

COPYRIGHT
       Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com.  See the license file
       included in the distribution for a complete license statement.

AUTHOR
       Generated automatically from the source code.

BUGS
       If you find a bug in Qt, please report it as described in
       http://doc.trolltech.com/bughowto.html.	Good bug reports help us to help you. Thank you.

       The definitive Qt documentation is provided in HTML format; it is located at
       $QTDIR/doc/html and can be read using Qt Assistant or with a web browser. This man page is
       provided as a convenience for those users who prefer man pages, although this format is
       not officially supported by Trolltech.

       If you find errors in this manual page, please report them to qt-bugs@trolltech.com.
       Please include the name of the manual page (qvaluelist.3qt) and the Qt version (3.3.8).

Trolltech AS				 2 February 2007			  QValueList(3qt)
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