tqt3/doc/tqvaluelist.doc

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/*****************************************************************************
  TQValueList documentation
 *****************************************************************************/

/*!
    \class TQValueList tqvaluelist.h
    \brief The TQValueList class is a value-based template class that
    provides lists.

    \ingroup qtl
    \ingroup tools
    \ingroup shared
    \mainclass
    \reentrant

    TQValueList is a TQt implementation of an STL-like list container.
    It can be used in your application if the standard \c list is not
    available for your target platform(s). TQValueList is part of the
    \link ntqtl.html TQt Template Library\endlink.

    TQValueList\<T\> defines a template instance to create a list of
    values that all have the class T. Note that TQValueList 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"; TQPtrList and TQDict are "pointer based".

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

    Some classes cannot be used within a TQValueList, for example, all
    classes derived from TQObject and thus all classes that implement
    widgets. Only values can be used in a TQValueList. 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.

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

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

    Example:
    \code
    class Employee
    {
    public:
	Employee(): sn(0) {}
	Employee( const TQString& forename, const TQString& surname, int salary )
	    : fn(forename), sn(surname), sal(salary)
	{}

	TQString forename() const { return fn; }
	TQString surname() const { return sn; }
	int salary() const { return sal; }
	void setSalary( int salary ) { sal = salary; }

    private:
	TQString fn;
	TQString sn;
	int sal;
    };

    typedef TQValueList<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
    \endcode


    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 \e past the last item in the
    container. The past-the-end iterator is still associated with the
    list it belongs to, however it is \e 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 \link
    ntqtl.html#qFind tqFind()\endlink algorithm. For example:

    \code
    TQValueList<int> list;
    ...
    TQValueList<int>::iterator it = tqFind( list.begin(), list.end(), 3 );
    if ( it != list.end() )
	// it points to the found item
    \endcode

    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:

    \code
    TQValueList<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;
    }
    ...
    TQValueList<double> dlist;
    double d = dlist.last(); // undefined
    \endcode

    Because TQValueList 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().

    TQValueList is shared implicitly, which means it can be copied in
    constant time, i.e. O(1). If multiple TQValueList 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 TQValueList is being used in a
    multi-threaded program, you must protect all access to the list.
    See \l TQMutex.

    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 \link ntqtl.html TQt Template
    Library\endlink. For example with qHeapSort():

    Example:
    \code
    TQValueList<int> list;
    list.append( 5 );
    list.append( 8 );
    list.append( 3 );
    list.append( 4 );
    qHeapSort( list );
    \endcode

    \sa TQValueListIterator
*/

/*! \enum TQValueList::iterator
	The list's iterator type, TQValueListIterator. */
/*! \enum TQValueList::const_iterator
	The list's const iterator type, TQValueListConstIterator. */
/*! \enum TQValueList::value_type
	The type of the object stored in the list, T. */
/*! \enum TQValueList::pointer
	The pointer to T type. */
/*! \enum TQValueList::const_pointer
	The const pointer to T type. */
/*! \enum TQValueList::reference
	The reference to T type. */
/*! \enum TQValueList::const_reference
	The const reference to T type. */
/*! \enum TQValueList::size_type
	An unsigned integral type, used to represent various sizes. */
/*! \enum TQValueList::difference_type
    \internal
*/
/*! \enum TQValueList::ValueType
    \internal
*/
/*!
    \fn TQValueList::TQValueList()

    Constructs an empty list.
*/

/*!
    \fn TQValueList::TQValueList( const TQValueList<T>& l )

    Constructs a copy of \a l.

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

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

/*!
    \fn TQValueList::TQValueList( const std::list<T>& l )

    Contructs a copy of \a l.

    This constructor is provided for compatibility with STL
    containers.
*/

/*!
    \fn TQValueList::~TQValueList()

    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:
    TQValueList is highly tuned for performance, not for error
    checking.
*/

/*! \enum  TQValueListIterator::NodePtr
	\internal */
/*! \enum  TQValueListIterator::iterator_category
	\internal */
/*! \enum  TQValueListIterator::size_type
	\internal */
/*! \enum  TQValueListIterator::difference_type
	\internal */
/*!
    \fn TQValueListIterator::TQValueListIterator( NodePtr p )
    \internal
*/

/*!
    \fn bool TQValueList::operator== ( const TQValueList<T>& l ) const

    Compares both lists.

    Returns TRUE if this list and \a l are equal; otherwise returns
    FALSE.
*/

/*!
    \fn bool TQValueList::operator== ( const std::list<T>& l ) const

    \overload

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

    This operator is provided for compatibility with STL containers.
*/

/*!
    \fn TQValueList<T>& TQValueList::operator= ( const TQValueList<T>& l )

    Assigns \a 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 TQValueList
    is implicitly shared.
*/

/*!
    \fn TQValueList<T>& TQValueList::operator= ( const std::list<T>& l )

    \overload

    Assigns the contents of \a l to the list.

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

/*!
    \fn bool TQValueList::operator!= ( const TQValueList<T>& l ) const

    Compares both lists.

    Returns TRUE if this list and \a l are unequal; otherwise returns
    FALSE.
*/

/*!
    \fn iterator TQValueList::insert( iterator it, const T& x )

    Inserts the value \a x in front of the item pointed to by the
    iterator, \a it.

    Returns an iterator pointing at the inserted item.

    \sa append(), prepend()
*/

/*!
    \fn uint TQValueList::remove( const T& x )

    \overload

    Removes all items that have value \a x and returns the number of
    removed items.
*/

/*!
    \fn void TQValueList::clear()

    Removes all items from the list.

    \sa remove()
*/

/*!
    \fn iterator TQValueList::begin()

    \overload

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

    \sa first(), end()
*/

/*!
    \fn const_iterator TQValueList::begin() const

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

    \sa first(), end(), constBegin()
*/

/*!
    \fn const_iterator TQValueList::constBegin() const

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

    \sa begin()
*/

/*!
    \fn iterator TQValueList::end()

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

    \sa last(), begin(), constEnd()
*/

/*!
    \fn const_iterator TQValueList::end() const

    \overload

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

    \sa last(), begin()
*/

/*!
    \fn const_iterator TQValueList::constEnd() const

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

    \sa end()
*/

/*!
    \fn QDataStream& operator>>( QDataStream& s, TQValueList<T>& l )

    \relates TQValueList

    Reads a list, \a l, from the stream \a s. The type T stored in the
    list must implement the streaming operator.
*/

/*!
    \fn QDataStream& operator<<( QDataStream& s, const TQValueList<T>& l )

    \overload
    \relates TQValueList

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

/*!
    \fn size_type TQValueList::size() const

    Returns the number of items in the list.

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

    \sa empty()
*/

/*!
    \fn bool TQValueList::empty() const

    Returns TRUE if the list contains no items; otherwise returns
    FALSE.

    \sa size()
*/

/*!
    \fn void TQValueList::push_front( const T& x )

    Inserts \a x at the beginning of the list.

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

/*!
    \fn void TQValueList::push_back( const T& x )

    Inserts \a x at the end of the list.

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

/*!
    \fn iterator TQValueList::erase( iterator it )

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

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

/*!
    \fn iterator TQValueList::erase( iterator first, iterator last )

    \overload

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

/*!
    \fn reference TQValueList::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().

    \sa back()
*/

/*!
    \fn const_reference TQValueList::front() const

    \overload
*/

/*!
    \fn reference TQValueList::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().

    \sa front()
*/

/*!
    \fn const_reference TQValueList::back() const

    \overload
*/

/*!
    \fn void TQValueList::pop_front()

    Removes the first item. If there is no first item, this operation
    is undefined.

    This function is provided for STL compatibility.
*/

/*!
    \fn void TQValueList::pop_back()

    Removes the last item. If there is no last item, this operation is
    undefined.

    This function is provided for STL compatibility.
*/

/*!
    \fn void TQValueList::insert( iterator pos, size_type n, const T& x )

    \overload

    Inserts \a n copies of \a x before position \a pos.
*/

/*!
  \fn void TQValueList::detach()
  \internal
*/

/*!
    \fn TQValueList<T>& TQValueList::operator<< ( const T& x )

    Adds the value \a x to the end of the list.

    Returns a reference to the list.
*/

/*!
    \fn const T& TQValueList::operator[] ( size_type i ) const

    Returns a const reference to the item with index \a 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 \a 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. TQValueList is not optimized for random item
    access. If you need random access use a different container, such
    as TQValueVector.
*/

/*!
    \fn T& TQValueList::operator[] ( size_type i )

    \overload

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

/*!
    \fn const_iterator TQValueList::at( size_type i ) const

    Returns an iterator pointing to the item at position \a 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. TQValueList is not optimized for random item
    access. If you need random access use a different container, such
    as TQValueVector.
*/

/*!
    \fn iterator TQValueList::at( size_type i )

    \overload

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

*/

/*!
    \fn iterator TQValueList::fromLast()

    \overload

    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:

    \code
    TQValueList<int> l;
    ...
    TQValueList<int>::iterator it = l.end();
    --it;
    if ( it != end() )
	// ...
    \endcode

*/

/*!
    \fn const_iterator TQValueList::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:

    \code
    TQValueList<int> l;
    ...
    TQValueList<int>::iterator it = l.end();
    --it;
    if ( it != end() )
	// ...
    \endcode

*/

/*!
    \fn TQValueList<T> TQValueList::operator+( const TQValueList<T>& l ) const

    Creates a new list and fills it with the items of this list. Then
    the items of \a l are appended. Returns the new list.
*/

/*!
    \fn TQValueList<T>& TQValueList::operator+= ( const TQValueList<T>& l )

    Appends the items of \a l to this list. Returns a reference to
    this list.
*/

/*!
    \fn TQValueList<T>& TQValueList::operator+= ( const T& x )

    \overload

    Appends the value \a x to the list. Returns a reference to the
    list.
*/

/*!
    \fn uint TQValueList::count() const

    Returns the number of items in the list.

    \sa isEmpty()
*/

/*!
    \fn bool TQValueList::isEmpty() const

    Returns TRUE if the list contains no items; otherwise returns
    FALSE.

    \sa count()
*/

/*!
    \fn iterator TQValueList::append( const T& x )

    Inserts \a x at the end of the list.

    \sa insert(), prepend()
*/

/*!
    \fn iterator TQValueList::prepend( const T& x )

    Inserts \a x at the beginning of the list.

    \sa insert(), append()
*/

/*!
    \fn iterator TQValueList::remove( iterator it )

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

    \sa clear()
*/

/*!
    \fn iterator TQValueList::find( const T& x )

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

    Returns end() is no item matched.
*/

/*!
    \fn const_iterator TQValueList::find( const T& x ) const

    \overload

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

    Returns end() if no item matched.
*/

/*!
    \fn iterator TQValueList::find( iterator it, const T& x )

    \overload

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

    Returns end() if no item matched.
*/

/*!
    \fn const_iterator TQValueList::find( const_iterator it, const T& x ) const

    \overload

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

    Returns end() if no item matched.
*/

/*!
    \fn uint TQValueList::contains( const T& x ) const

    Returns the number of occurrences of the value \a x in the list.
*/

/*!
    \fn int TQValueList::findIndex( const T& x ) const

    Returns the index of the first occurrence of the value \a x.
    Returns -1 if no item matched.
*/

/*!
    \fn T& TQValueList::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.

    \sa last()
*/

/*!
    \fn const T& TQValueList::first() const

    \overload
*/

/*!
    \fn T& TQValueList::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.
*/

/*!
    \fn const T& TQValueList::last() const

    \overload
*/

/*****************************************************************************
  TQValueListIterator documentation
 *****************************************************************************/

/*!
    \class TQValueListIterator tqvaluelist.h
    \brief The TQValueListIterator class provides an iterator for TQValueList.

    \ingroup qtl
    \ingroup tools
    \reentrant

    An iterator is a class for accessing the items of a container
    class: a generalization of the index in an array. A pointer
    into a "const char *" and an index into an "int[]" are both
    iterators, and the general idea is to provide that functionality
    for any data structure.

    The TQValueListIterator class is an iterator for TQValueList
    instantiations. You can create the appropriate iterator type by
    using the \c iterator typedef provided by TQValueList.

    The only way to access the items in a TQValueList is to use an
    iterator.

    Example (see TQValueList for the complete code):
    \code
    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
    \endcode

    TQValueList is highly optimized for performance and memory usage.
    This means that you must be careful: TQValueList does not know
    about all its iterators and the iterators don't know to which list
    they belong. This makes things very fast, but if you're not
    careful, you can get spectacular bugs. Always make sure iterators
    are valid before dereferencing them or using them as parameters to
    generic algorithms in the STL or the \link ntqtl.html QTL\endlink.

    Using an invalid iterator is undefined (your application will
    probably crash). Many TQt functions return const value lists; to
    iterate over these you should make a copy and iterate over the
    copy.

    For every Iterator there is a ConstIterator. When accessing a
    TQValueList in a const environment or if the reference or pointer
    to the list is itself const, then you must use the ConstIterator.
    Its semantics are the same as the Iterator, but it only returns
    const references.

    \sa TQValueList, TQValueListConstIterator
*/

/*! \enum  TQValueListIterator::value_type
	The type of value, T. */
/*! \enum  TQValueListIterator::pointer
	Pointer to value_type. */
/*! \enum  TQValueListIterator::reference
	Reference to value_type. */

/*!
    \fn TQValueListIterator::TQValueListIterator()

    Creates un uninitialized iterator.
*/

/*
    \fn TQValueListIterator::TQValueListIterator( NodePtr p )

    \overload

    \internal
*/

/*!
    \fn TQValueListIterator::TQValueListIterator( const TQValueListIterator<T>& it )

    \overload

    Constructs a copy of the iterator \a it.
*/

/* Unfortunately not with MSVC
  \fn T *TQValueListIterator::operator->()
  Pointer operator. Returns a pointer to the current iterator item.
  The great advantage of this operator is that you can treat the
  iterator like a pointer.

  Example:
  \code
    TQValueList<int>::Iterator it = list.begin();
    for( ; it != end(); ++it )
	it->show();
  \endcode
*/

/*!
    \fn T& TQValueListIterator::operator*()

    Asterisk operator. Returns a reference to the current iterator item.
*/

/*!
    \fn const T& TQValueListIterator::operator*() const

    \overload

    Asterisk operator. Returns a reference to the current iterator item.
*/

/*!
    \fn TQValueListIterator<T>& TQValueListIterator::operator++()

    Prefix ++ makes the succeeding item current and returns an
    iterator pointing to the new current item. The iterator cannot
    check whether it reached the end of the list. Incrementing the
    iterator returned by end() causes undefined results.
*/

/*!
    \fn TQValueListIterator<T> TQValueListIterator::operator++(int)

    \overload

    Postfix ++ makes the succeeding item current and returns an
    iterator pointing to the new current item. The iterator cannot
    check whether it reached the end of the list. Incrementing the
    iterator returned by end() causes undefined results.
*/

/*!
    \fn TQValueListIterator<T>& TQValueListIterator::operator--()

    Prefix -- makes the previous item current and returns an iterator
    pointing to the new current item. The iterator cannot check
    whether it reached the beginning of the list. Decrementing the
    iterator returned by begin() causes undefined results.
*/

/*!
    \fn TQValueListIterator<T> TQValueListIterator::operator--(int)

    \overload

    Postfix -- makes the previous item current and returns an iterator
    pointing to the new current item. The iterator cannot check
    whether it reached the beginning of the list. Decrementing the
    iterator returned by begin() causes undefined results.
*/


/*!
    \fn TQValueListIterator<T>& TQValueListIterator::operator+=(int j)

    Postfix -- jumps \a j steps forward in the list. The iterator
    cannot check whether it reached the end of the list. Jumping past
    the end() causes undefined results.
*/

/*!
    \fn TQValueListIterator<T>& TQValueListIterator::operator-=(int j)

    Postfix -- jumps \a j steps backward in the list. The iterator
    cannot check whether it reached the beginning of the list. Jumping
    past begin() causes undefined results.
*/

/*!
    \fn bool TQValueListIterator::operator==( const TQValueListIterator<T>& it ) const

    Compares this iterator and \a it and returns TRUE if they point to
    the same item; otherwise returns FALSE.
*/

/*!
    \fn bool TQValueListIterator::operator!=( const TQValueListIterator<T>& it ) const

    Compares this iterator and \a it and returns TRUE if they point to
    different items; otherwise returns FALSE.
*/

/*****************************************************************************
  TQValueListConstIterator documentation
 *****************************************************************************/

/*!
    \class TQValueListConstIterator tqvaluelist.h
    \brief The TQValueListConstIterator class provides a const iterator
    for TQValueList.

    \ingroup qtl
    \ingroup tools
    \reentrant

    In contrast to TQValueListIterator, this class is used to iterate
    over a const list. It does not allow modification of the values of
    the list since that would break const semantics.

    You can create the appropriate const iterator type by using the \c
    const_iterator typedef provided by TQValueList.

    For more information on TQValueList iterators, see
    TQValueListIterator.

    \sa TQValueListIterator, TQValueList
*/

/*! \enum  TQValueListConstIterator::value_type
	The type of value. */
/*! \enum  TQValueListConstIterator::pointer
	Pointer to value_type. */
/*! \enum  TQValueListConstIterator::reference
	Reference to value_type. */
/*! \enum  TQValueListConstIterator::NodePtr
	\internal */
/*! \enum  TQValueListConstIterator::iterator_category
	\internal */
/*! \enum  TQValueListConstIterator::size_type
	\internal */
/*! \enum  TQValueListConstIterator::difference_type
	\internal */

/*!
    \fn TQValueListConstIterator::TQValueListConstIterator()

    Creates un uninitialized iterator.
*/

/*!
    \fn TQValueListConstIterator::TQValueListConstIterator( NodePtr p )

    \overload

    \internal
*/

/*!
    \fn TQValueListConstIterator::TQValueListConstIterator( const TQValueListConstIterator<T>& it )

    \overload

    Constructs a copy of the iterator \a it.
*/

/*!
    \fn TQValueListConstIterator::TQValueListConstIterator( const TQValueListIterator<T>& it )

    Constructs a copy of the iterator \a it.
*/

/* Unfortunately not with MSVC
  \fn const T *TQValueListConstIterator::operator->()
  Pointer operator. Returns a pointer to the current iterator item.
  The great advantage of this operator is that you can treat the
  iterator like a pointer.

  Example:
  \code
    TQValueList<int>::Iterator it = list.begin();
    for( ; it != end(); ++it )
	it->show();
  \endcode
*/

/*!
    \fn const T& TQValueListConstIterator::operator*() const

    Asterisk operator. Returns a reference to the current iterator item.
*/

/*!
    \fn TQValueListConstIterator<T>& TQValueListConstIterator::operator++()

    Prefix ++ makes the succeeding item current and returns an
    iterator pointing to the new current item. The iterator cannot
    check whether it reached the end of the list. Incrementing the
    iterator returned by end() causes undefined results.
*/

/*!
    \fn TQValueListConstIterator<T> TQValueListConstIterator::operator++(int)

    \overload

    Postfix ++ makes the succeeding item current and returns an
    iterator pointing to the new current item. The iterator cannot
    check whether it reached the end of the list. Incrementing the
    iterator returned by end() causes undefined results.
*/

/*!
    \fn TQValueListConstIterator<T>& TQValueListConstIterator::operator--()

    Prefix -- makes the previous item current and returns an iterator
    pointing to the new current item. The iterator cannot check
    whether it reached the beginning of the list. Decrementing the
    iterator returned by begin() causes undefined results.
*/

/*!
    \fn TQValueListConstIterator<T> TQValueListConstIterator::operator--(int)

    \overload

    Postfix -- makes the previous item current and returns an iterator
    pointing to the new current item. The iterator cannot check
    whether it reached the beginning of the list. Decrementing the
    iterator returned by begin() causes undefined results.
*/

/*!
    \fn bool TQValueListConstIterator::operator==( const TQValueListConstIterator<T>& it ) const

    Compares this iterator with \a it and returns TRUE if they point
    to the same item; otherwise returns FALSE.
*/

/*!
    \fn bool TQValueListConstIterator::operator!=( const TQValueListConstIterator<T>& it ) const

    Compares this iterator with \a it and returns TRUE if they point
    to different items; otherwise returns FALSE.
*/


/*!
    \enum TQValueList::Iterator

    This iterator is an instantiation of TQValueListIterator for the
    same type as this TQValueList. In other words, if you instantiate
    TQValueList<int>, Iterator is a TQValueListIterator<int>. Several
    member function use it, such as TQValueList::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.

    \sa TQValueListIterator ConstIterator
*/

/*!
    \enum TQValueList::ConstIterator

    This iterator is an instantiation of TQValueListConstIterator for
    the same type as this TQValueList. In other words, if you
    instantiate TQValueList<int>, ConstIterator is a
    TQValueListConstIterator<int>. Several member function use it, such
    as TQValueList::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.

    \sa TQValueListIterator Iterator
*/