path: root/doc/tqptrlist.doc

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/*****************************************************************************
  TQPtrList documentation
 *****************************************************************************/

/*!
    \class TQPtrList
    \brief The TQPtrList class is a template class that provides a list.

    \ingroup collection
    \ingroup tools

    \important autoDelete setAutoDelete

    TQValueList is an STL-compatible alternative to this class.

    Define a template instance TQPtrList\<X\> to create a list that
    operates on pointers to X (X*).

    The list class is indexable and has a \link at() current
    index\endlink and a \link current() current item\endlink. The
    first item corresponds to index position 0. The current index is
    -1 if the current item is 0.

    Items are inserted with prepend(), insert() or append(). Items are
    removed with remove(), removeRef(), removeFirst() and
    removeLast(). You can search for an item using find(), findNext(),
    findRef() or findNextRef(). The list can be sorted with sort().
    You can count the number of occurrences of an item with contains()
    or containsRef(). You can get a pointer to the current item with
    current(), to an item at a particular index position in the list
    with at() or to the first or last item with getFirst() and
    getLast(). You can also iterate over the list with first(),
    last(), next() and prev() (which all update current()). The list's
    deletion property is set with setAutoDelete().

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

	void setSalary( int salary ) { sal = salary; }

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

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

    TQPtrList<Employee> list;
    list.setAutoDelete( TRUE ); // the list owns the objects

    list.append( new Employee("John", "Doe", 50000) );
    list.append( new Employee("Jane", "Williams", 80000) );
    list.append( new Employee("Tom", "Jones", 60000) );

    Employee *employee;
    for ( employee = list.first(); employee; employee = list.next() )
	cout << employee->surname().latin1() << ", " <<
		employee->forename().latin1() << " earns " <<
		employee->salary() << endl;
    cout << endl;

    // very inefficient for big lists
    for ( uint i = 0; i < list.count(); ++i )
	if ( list.at(i) )
	    cout << list.at( i )->surname().latin1() << endl;
    \endcode

    The output is
    \code
    Doe, John earns 50000
    Williams, Jane earns 80000
    Jones, Tom earns 60000

    Doe
    Williams
    Jones
    \endcode

    TQPtrList has several member functions for traversing the list, but
    using a TQPtrListIterator can be more practical. Multiple list
    iterators may traverse the same list, independently of each other
    and of the current list item.

    In the example above we make the call setAutoDelete(TRUE).
    Enabling auto-deletion tells the list to delete items that are
    removed. The default is to not delete items when they are removed
    but this would cause a memory leak in the example because there
    are no other references to the list items.

    When inserting an item into a list only the pointer is copied, not
    the item itself, i.e. a shallow copy. It is possible to make the
    list copy all of the item's data (deep copy) when an item is
    inserted. insert(), inSort() and append() call the virtual
    function TQPtrCollection::newItem() for the item to be inserted.
    Inherit a list and reimplement newItem() to have deep copies.

    When removing an item from a list, the virtual function
    TQPtrCollection::deleteItem() is called. TQPtrList's default
    implementation is to delete the item if auto-deletion is enabled.

    The virtual function compareItems() can be reimplemented to
    compare two list items. This function is called from all list
    functions that need to compare list items, for instance
    remove(const type*). If you only want to deal with pointers, there
    are functions that compare pointers instead, for instance
    removeRef(const type*). These functions are somewhat faster than
    those that call compareItems().

    List items are stored as \c void* in an internal QLNode, which
    also holds pointers to the next and previous list items. The
    functions currentNode(), removeNode(), and takeNode() operate
    directly on the QLNode, but they should be used with care. The
    data component of the node is available through QLNode::getData().

    The TQStrList class defined in \l tqstrlist.h is a list of \c char*.
    It reimplements newItem(), deleteItem() and compareItems(). (But
    see TQStringList for a list of Unicode TQStrings.)

    \sa TQPtrListIterator
*/


/*!
    \fn TQPtrList::TQPtrList()

    Constructs an empty list.
*/

/*!
    \fn TQPtrList::TQPtrList( const TQPtrList<type> &list )

    Constructs a copy of \a list.

    Each item in \a list is \link append() appended\endlink to this
    list. Only the pointers are copied (shallow copy).
*/

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

    Removes all items from the list and destroys the list.

    All list iterators that access this list will be reset.

    \sa setAutoDelete()
*/

/*!
    \fn TQPtrList<type> &TQPtrList::operator=(const TQPtrList<type> &list)

    Assigns \a list to this list and returns a reference to this list.

    This list is first cleared and then each item in \a list is \link
    append() appended\endlink to this list. Only the pointers are
    copied (shallow copy) unless newItem() has been reimplemented.
*/

/*!
    \fn bool TQPtrList::operator==(const TQPtrList<type> &list ) const

    Compares this list with \a list. Returns TRUE if the lists contain
    the same data; otherwise returns FALSE.
*/

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

    Returns the number of items in the list.

    \sa isEmpty()
*/

/*!
    \fn bool TQPtrList::operator!=(const TQPtrList<type> &list ) const

    Compares this list with \a list. Returns TRUE if the lists contain
    different data; otherwise returns FALSE.
*/


/*!
    \fn void TQPtrList::sort()

    Sorts the list by the result of the virtual compareItems()
    function.

    The heap sort algorithm is used for sorting. It sorts n items with
    O(n*log n) comparisons. This is the asymptotic optimal solution of
    the sorting problem.

    \sa inSort()
*/

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

    Returns TRUE if the list is empty; otherwise returns FALSE.

    \sa count()
*/

/*!
    \fn bool TQPtrList::insert( uint index, const type *item )

    Inserts the \a item at position \a index in the list.

    Returns TRUE if successful, i.e. if \a index is in range;
    otherwise returns FALSE. The valid range is 0 to count()
    (inclusively). The item is appended if \a index == count().

    The inserted item becomes the current list item.

    \a item must not be 0.

    \sa append(), current(), replace()
*/

/*!
    \fn bool TQPtrList::replace( uint index, const type *item )

    Replaces the item at position \a index with the new \a item. 

    Returns TRUE if successful, i.e. \a index is in the range 0 to
    count()-1.

    \sa append(), current(), insert()
*/

/*!
    \fn void TQPtrList::inSort( const type *item )

    Inserts the \a item at its sorted position in the list.

    The sort order depends on the virtual compareItems() function. All
    items must be inserted with inSort() to maintain the sorting
    order.

    The inserted item becomes the current list item.

    \a item must not be 0.

    \warning Using inSort() is slow. An alternative, especially if you
    have lots of items, is to simply append() or insert() them and
    then use sort(). inSort() takes up to O(n) compares. That means
    inserting n items in your list will need O(n^2) compares whereas
    sort() only needs O(n*log n) for the same task. So use inSort()
    only if you already have a presorted list and want to insert just
    a few additional items.

    \sa insert(), compareItems(), current(), sort()
*/

/*!
    \fn void TQPtrList::append( const type *item )

    Inserts the \a item at the end of the list.

    The inserted item becomes the current list item. This is
    equivalent to \c{insert( count(), item )}.

    \a item must not be 0.

    \sa insert(), current(), prepend()
*/

/*!
    \fn void TQPtrList::prepend( const type *item )

    Inserts the \a item at the start of the list.

    The inserted item becomes the current list item. This is
    equivalent to \c{insert( 0, item )}.

    \a item must not be 0.

    \sa append(), insert(), current()
*/

/*!
    \fn bool TQPtrList::remove( uint index )

    Removes the item at position \a index in the list.

    Returns TRUE if successful, i.e. if \a index is in range;
    otherwise returns FALSE. The valid range is \c{0..(count() - 1)}
    inclusive.

    The removed item is deleted if \link setAutoDelete()
    auto-deletion\endlink is enabled.

    The item after the removed item becomes the new current list item
    if the removed item is not the last item in the list. If the last
    item is removed, the new last item becomes the current item.

    All list iterators that refer to the removed item will be set to
    point to the new current item.

    \sa take(), clear(), setAutoDelete(), current() removeRef()
*/

/*!
    \fn bool TQPtrList::remove()

    \overload

    Removes the current list item.

    Returns TRUE if successful, i.e. if the current item isn't 0;
    otherwise returns FALSE.

    The removed item is deleted if \link setAutoDelete()
    auto-deletion\endlink is enabled.

    The item after the removed item becomes the new current list item
    if the removed item is not the last item in the list. If the last
    item is removed, the new last item becomes the current item. The
    current item is set to 0 if the list becomes empty.

    All list iterators that refer to the removed item will be set to
    point to the new current item.

    \sa take(), clear(), setAutoDelete(), current() removeRef()
*/

/*!
    \fn bool TQPtrList::remove( const type *item )

    \overload

    Removes the first occurrence of \a item from the list.

    Returns TRUE if successful, i.e. if \a item is in the list;
    otherwise returns FALSE.

    The removed item is deleted if \link setAutoDelete()
    auto-deletion\endlink is enabled.

    The compareItems() function is called when searching for the item
    in the list. If compareItems() is not reimplemented, it is more
    efficient to call removeRef().

    If \a item is NULL then the current item is removed from the list.

    The item after the removed item becomes the new current list item
    if the removed item is not the last item in the list. If the last
    item is removed, the new last item becomes the current item. The
    current item is set to 0 if the list becomes empty.

    All list iterators that refer to the removed item will be set to
    point to the new current item.

    \sa removeRef(), take(), clear(), setAutoDelete(), compareItems(),
    current()
*/

/*!
    \fn bool TQPtrList::removeRef( const type *item )

    Removes the first occurrence of \a item from the list.

    Returns TRUE if successful, i.e. if \a item is in the list;
    otherwise returns FALSE.

    The removed item is deleted if \link setAutoDelete()
    auto-deletion\endlink is enabled.

    Equivalent to:
    \code
	if ( list.findRef( item ) != -1 )
	    list.remove();
    \endcode

    The item after the removed item becomes the new current list item
    if the removed item is not the last item in the list. If the last
    item is removed, the new last item becomes the current item. The
    current item is set to 0 if the list becomes empty.

    All list iterators that refer to the removed item will be set to
    point to the new current item.

    \sa remove(), clear(), setAutoDelete(), current()
*/

/*!
    \fn void TQPtrList::removeNode( QLNode *node )

    Removes the \a node from the list.

    This node must exist in the list, otherwise the program may crash.

    The removed item is deleted if \link setAutoDelete()
    auto-deletion\endlink is enabled.

    The first item in the list will become the new current list item.
    The current item is set to 0 if the list becomes empty.

    All list iterators that refer to the removed item will be set to
    point to the item succeeding this item or to the preceding item if
    the removed item was the last item.

    \warning Do not call this function unless you are an expert.

    \sa takeNode(), currentNode() remove() removeRef()
*/

/*!
    \fn bool TQPtrList::removeFirst()

    Removes the first item from the list. Returns TRUE if successful,
    i.e. if the list isn't empty; otherwise returns FALSE.

    The removed item is deleted if \link setAutoDelete()
    auto-deletion\endlink is enabled.

    The first item in the list becomes the new current list item. The
    current item is set to 0 if the list becomes empty.

    All list iterators that refer to the removed item will be set to
    point to the new current item.

    \sa removeLast(), setAutoDelete(), current() remove()
*/

/*!
    \fn bool TQPtrList::removeLast()

    Removes the last item from the list. Returns TRUE if successful,
    i.e. if the list isn't empty; otherwise returns FALSE.

    The removed item is deleted if \link setAutoDelete()
    auto-deletion\endlink is enabled.

    The last item in the list becomes the new current list item. The
    current item is set to 0 if the list becomes empty.

    All list iterators that refer to the removed item will be set to
    point to the new current item.

    \sa removeFirst(), setAutoDelete(), current()
*/

/*!
    \fn type *TQPtrList::take( uint index )

    Takes the item at position \a index out of the list without
    deleting it (even if \link setAutoDelete() auto-deletion\endlink
    is enabled).

    Returns a pointer to the item taken out of the list, or 0 if the
    index is out of range. The valid range is \c{0..(count() - 1)}
    inclusive.

    The item after the removed item becomes the new current list item
    if the removed item is not the last item in the list. If the last
    item is removed, the new last item becomes the current item. The
    current item is set to 0 if the list becomes empty.

    All list iterators that refer to the taken item will be set to
    point to the new current item.

    \sa remove(), clear(), current()
*/

/*!
    \fn type *TQPtrList::take()

    \overload

    Takes the current item out of the list without deleting it (even
    if \link setAutoDelete() auto-deletion\endlink is enabled).

    Returns a pointer to the item taken out of the list, or 0 if
    the current item is 0.

    The item after the removed item becomes the new current list item
    if the removed item is not the last item in the list. If the last
    item is removed, the new last item becomes the current item. The
    current item is set to 0 if the list becomes empty.

    All list iterators that refer to the taken item will be set to
    point to the new current item.

    \sa remove(), clear(), current()
*/

/*!
    \fn type *TQPtrList::takeNode( QLNode *node )

    Takes the \a node out of the list without deleting its item (even
    if \link setAutoDelete() auto-deletion\endlink is enabled).
    Returns a pointer to the item taken out of the list.

    This node must exist in the list, otherwise the program may crash.

    The first item in the list becomes the new current list item.

    All list iterators that refer to the taken item will be set to
    point to the item succeeding this item or to the preceding item if
    the taken item was the last item.

    \warning Do not call this function unless you are an expert.

    \sa removeNode(), currentNode()
*/

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

    Removes all items from the list.

    The removed items are deleted if \link setAutoDelete()
    auto-deletion\endlink is enabled.

    All list iterators that access this list will be reset.

    \sa remove(), take(), setAutoDelete()
*/

/*!
    \fn int TQPtrList::find( const type *item )

    Finds the first occurrence of \a item in the list.

    If the item is found, the list sets the current item to point to
    the found item and returns the index of this item. If the item is
    not found, the list sets the current item to 0, the current
    index to -1, and returns -1.

    The compareItems() function is called when searching for the item
    in the list. If compareItems() is not reimplemented, it is more
    efficient to call findRef().

    \sa findNext(), findRef(), compareItems(), current()
*/

/*!
    \fn int TQPtrList::findNext( const type *item )

    Finds the next occurrence of \a item in the list, starting from
    the current list item.

    If the item is found, the list sets the current item to point to
    the found item and returns the index of this item. If the item is
    not found, the list sets the current item to 0, the current
    index to -1, and returns -1.

    The compareItems() function is called when searching for the item
    in the list. If compareItems() is not reimplemented, it is more
    efficient to call findNextRef().

    \sa find(), findNextRef(), compareItems(), current()
*/

/*!
    \fn int TQPtrList::findRef( const type *item )

    Finds the first occurrence of \a item in the list.

    If the item is found, the list sets the current item to point to
    the found item and returns the index of this item. If the item is
    not found, the list sets the current item to 0, the current
    index to -1, and returns -1.

    Calling this function is much faster than find() because find()
    compares \a item with each list item using compareItems(), whereas
    this function only compares the pointers.

    \sa findNextRef(), find(), current()
*/

/*!
    \fn int TQPtrList::findNextRef( const type *item )

    Finds the next occurrence of \a item in the list, starting from
    the current list item.

    If the item is found, the list sets the current item to point to
    the found item and returns the index of this item. If the item is
    not found, the list sets the current item to 0, the current
    index to -1, and returns -1.

    Calling this function is much faster than findNext() because
    findNext() compares \a item with each list item using
    compareItems(), whereas this function only compares the pointers.

    \sa findRef(), findNext(), current()
*/

/*!
    \fn uint TQPtrList::contains( const type *item ) const

    Returns the number of occurrences of \a item in the list.

    The compareItems() function is called when looking for the \a item
    in the list. If compareItems() is not reimplemented, it is more
    efficient to call containsRef().

    This function does not affect the current list item.

    \sa containsRef(), compareItems()
*/

/*!
    \fn uint TQPtrList::containsRef( const type *item ) const

    Returns the number of occurrences of \a item in the list.

    Calling this function is much faster than contains() because
    contains() compares \a item with each list item using
    compareItems(), whereas his function only compares the pointers.

    This function does not affect the current list item.

    \sa contains()
*/

/*!
    \fn type *TQPtrList::at( uint index )

    Returns a pointer to the item at position \a index in the list, or
    0 if the index is out of range.

    Sets the current list item to this item if \a index is valid. The
    valid range is \c{0..(count() - 1)} inclusive.

    This function is very efficient. It starts scanning from the first
    item, last item, or current item, whichever is closest to \a
    index.

    \sa current()
*/

/*!
    \fn int TQPtrList::at() const

    \overload

    Returns the index of the current list item. The returned value is
    -1 if the current item is 0.

    \sa current()
*/

/*!
    \fn type *TQPtrList::current() const

    Returns a pointer to the current list item. The current item may
    be 0 (implies that the current index is -1). 

    \sa at()
*/

/*!
    \fn QLNode *TQPtrList::currentNode() const

    Returns a pointer to the current list node.

    The node can be kept and removed later using removeNode(). The
    advantage is that the item can be removed directly without
    searching the list.

    \warning Do not call this function unless you are an expert.

    \sa removeNode(), takeNode(), current()
*/

/*!
    \fn type *TQPtrList::getFirst() const

    Returns a pointer to the first item in the list, or 0 if the list
    is empty.

    This function does not affect the current list item.

    \sa first(), getLast()
*/

/*!
    \fn type *TQPtrList::getLast() const

    Returns a pointer to the last item in the list, or 0 if the list
    is empty.

    This function does not affect the current list item.

    \sa last(), getFirst()
*/

/*!
    \fn type *TQPtrList::first()

    Returns a pointer to the first item in the list and makes this the
    current list item; returns 0 if the list is empty.

    \sa getFirst(), last(), next(), prev(), current()
*/

/*!
    \fn type *TQPtrList::last()

    Returns a pointer to the last item in the list and makes this the
    current list item; returns 0 if the list is empty.

    \sa getLast(), first(), next(), prev(), current()
*/

/*!
    \fn type *TQPtrList::next()

    Returns a pointer to the item succeeding the current item. Returns
    0 if the current item is 0 or equal to the last item.

    Makes the succeeding item current. If the current item before this
    function call was the last item, the current item will be set to
    0. If the current item was 0, this function does nothing.

    \sa first(), last(), prev(), current()
*/

/*!
    \fn type *TQPtrList::prev()

    Returns a pointer to the item preceding the current item. Returns
    0 if the current item is 0 or equal to the first item.

    Makes the preceding item current. If the current item before this
    function call was the first item, the current item will be set to
    0. If the current item was 0, this function does nothing.

    \sa first(), last(), next(), current()
*/

/*!
    \fn void TQPtrList::toVector( QGVector *vec ) const

    Stores all list items in the vector \a vec.

    The vector must be of the same item type, otherwise the result
    will be undefined.
*/

/*!
    \enum TQPtrList::iterator

    \internal
*/

/*!
    \enum TQPtrList::Iterator

    \internal
*/

/*!
    \enum TQPtrList::ConstIterator

    \internal
*/

/*!
    \enum TQPtrList::const_iterator

    \internal
*/

/*!
    \fn TQPtrList::constBegin() const

    \internal
*/

/*!
    \fn TQPtrList::constEnd() const

    \internal
*/

/*!
    \fn TQPtrList::erase(Iterator)

    \internal
*/


/*****************************************************************************
  TQPtrListIterator documentation
 *****************************************************************************/

/*!
    \class TQPtrListIterator
    \brief The TQPtrListIterator class provides an iterator for
    TQPtrList collections.

    \ingroup collection
    \ingroup tools

    Define a template instance TQPtrListIterator\<X\> to create a list
    iterator that operates on TQPtrList\<X\> (list of X*).

    The following example is similar to the \link
    tqptrlist.html#example example in the TQPtrList class documentation
    \endlink, but it uses TQPtrListIterator. The class Employee is
    defined there.

    \code
    TQPtrList<Employee> list;

    list.append( new Employee("John", "Doe", 50000) );
    list.append( new Employee("Jane", "Williams", 80000) );
    list.append( new Employee("Tom", "Jones", 60000) );

    TQPtrListIterator<Employee> it( list );
    Employee *employee;
    while ( (employee = it.current()) != 0 ) {
	++it;
	cout << employee->surname().latin1() << ", " <<
		employee->forename().latin1() << " earns " <<
		employee->salary() << endl;
    }
    \endcode

    The output is
    \code
    Doe, John earns 50000
    Williams, Jane earns 80000
    Jones, Tom earns 60000
    \endcode

    Using a list iterator is a more robust way of traversing the list
    than using the TQPtrList member functions \link TQPtrList::first()
    first\endlink(), \link TQPtrList::next() next\endlink(), \link
    TQPtrList::current() current\endlink(), etc., as many iterators can
    traverse the same list independently.

    An iterator has its own current list item and can get the next and
    previous list items. It doesn't modify the list in any way.

    When an item is removed from the list, all iterators that point to
    that item are updated to point to TQPtrList::current() instead to
    avoid dangling references.

    \sa TQPtrList
*/

/*!
    \fn TQPtrListIterator::TQPtrListIterator( const TQPtrList<type> &list )

    Constructs an iterator for \a list. The current iterator item is
    set to point on the first item in the \a list.
*/

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

    Destroys the iterator.
*/

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

    Returns the number of items in the list this iterator operates on.

    \sa isEmpty()
*/

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

    Returns TRUE if the list is empty; otherwise returns FALSE.

    \sa count()
*/

/*!
    \fn bool TQPtrListIterator::atFirst() const

    Returns TRUE if the current iterator item is the first list item;
    otherwise returns FALSE.

    \sa toFirst(), atLast()
*/

/*!
    \fn bool TQPtrListIterator::atLast() const

    Returns TRUE if the current iterator item is the last list item;
    otherwise returns FALSE.

    \sa toLast(), atFirst()
*/

/*!
    \fn type *TQPtrListIterator::toFirst()

    Sets the current iterator item to point to the first list item and
    returns a pointer to the item. Sets the current item to 0 and
    returns 0 if the list is empty.

    \sa toLast(), atFirst()
*/

/*!
    \fn type *TQPtrListIterator::toLast()

    Sets the current iterator item to point to the last list item and
    returns a pointer to the item. Sets the current item to 0 and
    returns 0 if the list is empty.

    \sa toFirst(), atLast()
*/

/*!
    \fn TQPtrListIterator::operator type *() const

    Cast operator. Returns a pointer to the current iterator item.
    Same as current().
*/

/*!
    \fn type *TQPtrListIterator::operator*()

    Asterisk operator. Returns a pointer to the current iterator item.
    Same as current().
*/

/*!
    \fn type *TQPtrListIterator::current() const

    Returns a pointer to the current iterator item. If the iterator is
    positioned before the first item in the list or after the last
    item in the list, 0 is returned.
*/

/*!
    \fn type *TQPtrListIterator::operator()()

    Makes the succeeding item current and returns the original current
    item.

    If the current iterator item was the last item in the list or if
    it was 0, 0 is returned.
*/

/*!
    \fn type *TQPtrListIterator::operator++()

    Prefix ++ makes the succeeding item current and returns the new
    current item.

    If the current iterator item was the last item in the list or if
    it was 0, 0 is returned.
*/

/*!
    \fn type *TQPtrListIterator::operator+=( uint jump )

    Sets the current item to the item \a jump positions after the
    current item and returns a pointer to that item.

    If that item is beyond the last item or if the list is empty, it
    sets the current item to 0 and returns 0
*/

/*!
    \fn type *TQPtrListIterator::operator--()

    Prefix - makes the preceding item current and returns the new
    current item.

    If the current iterator item was the first item in the list or if
    it was 0, 0 is returned.
*/

/*!
    \fn type *TQPtrListIterator::operator-=( uint jump )

    Returns the item \a jump positions before the current item or 0
    if it is beyond the first item. Makes this the current item.
*/

/*!
    \fn TQPtrListIterator<type>& TQPtrListIterator::operator=( const TQPtrListIterator<type> &it )

    Assignment. Makes a copy of the iterator \a it and returns a
    reference to this iterator.
*/


/*****************************************************************************
  TQStrList documentation
 *****************************************************************************/

/*!
    \class TQStrList tqstrlist.h
    \brief The TQStrList class provides a doubly-linked list of char*.

    \ingroup collection
    \ingroup tools
    \ingroup text

    If you want a string list of \l{TQString}s use TQStringList.

    This class is a TQPtrList\<char\> instance (a list of char*).

    TQStrList can make deep or shallow copies of the strings that are
    inserted.

    A deep copy means that memory is allocated for the string and then
    the string data is copied into that memory. A shallow copy is just
    a copy of the pointer value and not of the string data itself.

    The disadvantage of shallow copies is that because a pointer can
    be deleted only once, the program must put all strings in a
    central place and know when it is safe to delete them (i.e. when
    the strings are no longer referenced by other parts of the
    program). This can make the program more complex. The advantage of
    shallow copies is that they consume far less memory than deep
    copies. It is also much faster to copy a pointer (typically 4 or 8
    bytes) than to copy string data.

    A TQStrList that operates on deep copies will, by default, turn on
    auto-deletion (see setAutoDelete()). Thus, by default TQStrList
    will deallocate any string copies it allocates.

    The virtual compareItems() function is reimplemented and does a
    case-sensitive string comparison. The inSort() function will
    insert strings in sorted order. In general it is fastest to insert
    the strings as they come and sort() at the end; inSort() is useful
    when you just have to add a few extra strings to an already sorted
    list.

    The TQStrListIterator class is an iterator for TQStrList.
*/

/*!
    \fn TQStrList::TQStrList( bool deepCopies )

    Constructs an empty list of strings. Will make deep copies of all
    inserted strings if \a deepCopies is TRUE, or use shallow copies
    if \a deepCopies is FALSE.
*/

/*!
    \fn TQStrList::TQStrList( const TQStrList &list )

    Constructs a copy of \a list.

    If \a list has deep copies, this list will also get deep copies.
    Only the pointers are copied (shallow copy) if the other list does
    not use deep copies.
*/

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

    Destroys the list. All strings are removed.
*/

/*!
    \fn TQStrList& TQStrList::operator=( const TQStrList& list )

    Assigns \a list to this list and returns a reference to this list.

    If \a list has deep copies, this list will also get deep copies.
    Only the pointers are copied (shallow copy) if the other list does
    not use deep copies.
*/


/*****************************************************************************
  TQStrIList documentation
 *****************************************************************************/

/*!
    \class TQStrIList tqstrlist.h
    \brief The TQStrIList class provides a doubly-linked list of char*
    with case-insensitive comparison.

    \ingroup collection
    \ingroup tools

    This class is a TQPtrList\<char\> instance (a list of char*).

    TQStrIList is identical to TQStrList except that the virtual
    compareItems() function is reimplemented to compare strings
    case-insensitively. The inSort() function inserts strings in a
    sorted order. In general it is fastest to insert the strings as
    they come and sort() at the end; inSort() is useful when you just
    have to add a few extra strings to an already sorted list.

    The TQStrListIterator class works for TQStrIList.

    \sa TQStringList
*/

/*!
    \fn TQStrIList::TQStrIList( bool deepCopies )

    Constructs a list of strings. Will make deep copies of all
    inserted strings if \a deepCopies is TRUE, or use shallow copies
    if \a deepCopies is FALSE.
*/

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

    Destroys the list. All strings are removed.
*/

/*!
    \fn int TQPtrList::compareItems( TQPtrCollection::Item item1,
				    TQPtrCollection::Item item2 )

    This virtual function compares two list items.

    Returns:
    \list
    \i zero if \a item1 == \a item2
    \i nonzero if \a item1 != \a item2
    \endlist

    This function returns \e int rather than \e bool so that
    reimplementations can return three values and use it to sort by:

    \list
    \i 0 if \a item1 == \a item2
    \i \> 0 (positive integer) if \a item1 \> \a item2
    \i \< 0 (negative integer) if \a item1 \< \a item2
    \endlist

    inSort() requires that compareItems() is implemented as described
    here.

    This function should not modify the list because some const
    functions call compareItems().

    The default implementation compares the pointers.
*/

/*!
    \fn TQDataStream& TQPtrList::read( TQDataStream& s,
				    TQPtrCollection::Item& item )

    Reads a list item from the stream \a s and returns a reference to
    the stream.

    The default implementation sets \a item to 0.

    \sa write()
*/

/*!
    \fn TQDataStream& TQPtrList::write( TQDataStream& s,
					TQPtrCollection::Item item ) const

    Writes a list item, \a item to the stream \a s and returns a
    reference to the stream.

    The default implementation does nothing.

    \sa read()
*/

/*! \fn iterator TQPtrList::begin() 
\internal
*/
/*! \fn const_iterator TQPtrList::begin() const
\internal
*/
/*! \fn iterator TQPtrList::end() 
\internal
*/
/*! \fn const_iterator TQPtrList::end() const
\internal
*/

/*****************************************************************************
  TQStrListIterator documentation
 *****************************************************************************/

/*!
    \class TQStrListIterator tqstrlist.h
    \brief The TQStrListIterator class is an iterator for the TQStrList
    and TQStrIList classes.

    \ingroup tools

    This class is a TQPtrListIterator\<char\> instance. It can traverse
    the strings in the TQStrList and TQStrIList classes.
*/


/*****************************************************************************
  TQPtrListAutoDelete documentation
 *****************************************************************************/
/*
    \class TQPtrListAutoDelete
    \brief The TQPtrListAutoDelete class is a template class that provides a list that auto-deletes its data.

    \ingroup collection
    \ingroup tools

    A TQPtrListAutoDelete is identical to a TQPtrList with
    setAutoDelete(TRUE).
*/