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+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \class Q3MemArray
+ \brief The Q3MemArray class is a template class that provides arrays of simple types.
+ \compat
+
+ Q3MemArray is implemented as a template class. Define a template
+ instance Q3MemArray\<X\> to create an array that contains X items.
+
+ Q3MemArray stores the array elements directly in the array. It can
+ only deal with simple types (i.e. C++ types, structs, and classes
+ that have no constructors, destructors, or virtual functions).
+ Q3MemArray uses bitwise operations to copy and compare array
+ elements.
+
+ The Q3PtrVector collection class is also a kind of array. Like most
+ old Qt collection classes, it uses pointers to the contained items.
+
+ Q3MemArray uses explicit sharing with a
+ reference count. If more than one array shares common data and one
+ of the arrays is modified, all the arrays are modified.
+
+ The benefit of sharing is that a program does not need to duplicate
+ data when it is not required, which results in lower memory use
+ and less copying of data.
+
+ Example:
+ \snippet doc/src/snippets/code/doc_src_q3memarray.qdoc 0
+
+ Program output:
+ \snippet doc/src/snippets/code/doc_src_q3memarray.qdoc 1
+
+ Note concerning the use of Q3MemArray for manipulating structs or
+ classes: Compilers will often pad the size of structs of odd sizes
+ up to the nearest word boundary. This will then be the size
+ Q3MemArray will use for its bitwise element comparisons. Because
+ the remaining bytes will typically be uninitialized, this can
+ cause find() etc. to fail to find the element. Example:
+
+ \snippet doc/src/snippets/code/doc_src_q3memarray.qdoc 2
+
+ To work around this, make sure that you use a struct where
+ sizeof() returns the same as the sum of the sizes of the members
+ either by changing the types of the struct members or by adding
+ dummy members.
+
+ Q3MemArray data can be traversed by iterators (see begin() and
+ end()). The number of items is returned by count(). The array can
+ be resized with resize() and filled using fill().
+
+ You can make a shallow copy of the array with assign() (or
+ operator=()) and a deep copy with duplicate().
+
+ Search for values in the array with find() and contains(). For
+ sorted arrays (see sort()) you can search using bsearch().
+
+ You can set the data directly using setRawData() and
+ resetRawData(), although this requires care.
+*/
+
+/*! \fn Q3MemArray::operator QVector<type>() const
+
+ Automatically converts the Q3MemArray<type> into a QVector<type>.
+*/
+
+/*! \typedef Q3MemArray::Iterator
+ A Q3MemArray iterator.
+ \sa begin() end()
+*/
+/*! \typedef Q3MemArray::ConstIterator
+ A const Q3MemArray iterator.
+ \sa begin() end()
+*/
+/*! \typedef Q3MemArray::ValueType
+ \internal
+*/
+
+/*!
+ \fn Q3MemArray::Q3MemArray()
+
+ Constructs a null array.
+
+ \sa isNull()
+*/
+
+/*!
+ \fn Q3MemArray::Q3MemArray( int size )
+
+ Constructs an array with room for \a size elements. Makes a null
+ array if \a size == 0.
+
+ The elements are left uninitialized.
+
+ \sa resize(), isNull()
+*/
+
+/*!
+ \fn Q3MemArray::Q3MemArray( const Q3MemArray<type> &a )
+
+ Constructs a shallow copy of \a a.
+
+ \sa assign()
+*/
+
+/*!
+ \fn Q3MemArray::Q3MemArray(const QVector<type> &vector)
+
+ Constructs a copy of \a vector.
+*/
+
+/*!
+ \fn Q3MemArray::Q3MemArray(int arg1, int arg2)
+
+ Constructs an array \e{without allocating} array space. The
+ arguments \a arg1 and \a arg2 should be zero. Use at your own
+ risk.
+*/
+
+/*!
+ \fn Q3MemArray::~Q3MemArray()
+
+ Dereferences the array data and deletes it if this was the last
+ reference.
+*/
+
+/*!
+ \fn Q3MemArray<type> &Q3MemArray::operator=( const Q3MemArray<type> &a )
+
+ Assigns a shallow copy of \a a to this array and returns a
+ reference to this array.
+
+ Equivalent to assign( a ).
+*/
+
+/*!
+ \fn type *Q3MemArray::data() const
+
+ Returns a pointer to the actual array data.
+
+ The array is a null array if data() == 0 (null pointer).
+
+ \sa isNull()
+*/
+
+/*!
+ \fn uint Q3MemArray::nrefs() const
+
+ Returns the reference count for the shared array data. This
+ reference count is always greater than zero.
+*/
+
+/*!
+ \fn uint Q3MemArray::size() const
+
+ Returns the size of the array (maximum number of elements).
+
+ The array is a null array if size() == 0.
+
+ \sa isNull(), resize()
+*/
+
+/*!
+ \fn uint Q3MemArray::count() const
+
+ Returns the same as size().
+
+ \sa size()
+*/
+
+/*!
+ \fn bool Q3MemArray::isEmpty() const
+
+ Returns TRUE if the array is empty; otherwise returns FALSE.
+
+ isEmpty() is equivalent to isNull() for Q3MemArray (unlike
+ QString).
+*/
+
+/*!
+ \fn bool Q3MemArray::isNull() const
+
+ Returns TRUE if the array is null; otherwise returns FALSE.
+
+ A null array has size() == 0 and data() == 0.
+*/
+
+/*!
+ \fn bool Q3MemArray::resize( uint size, Optimization optim )
+
+ Resizes (expands or shrinks) the array to \a size elements. The
+ array becomes a null array if \a size == 0.
+
+ Returns TRUE if successful, or FALSE if the memory cannot be
+ allocated.
+
+ New elements are not initialized.
+
+ \a optim is either Q3GArray::MemOptim (the default) or
+ Q3GArray::SpeedOptim. When optimizing for speed rather than memory
+ consumption, the array uses a smart grow and shrink algorithm that
+ might allocate more memory than is actually needed for \a size
+ elements. This speeds up subsequent resize operations, for example
+ when appending many elements to an array, since the space has
+ already been allocated.
+
+ \sa size()
+*/
+
+/*!
+ \fn bool Q3MemArray::resize( uint size )
+
+ \overload
+
+ Resizes (expands or shrinks) the array to \a size elements. The
+ array becomes a null array if \a size == 0.
+
+ Returns TRUE if successful, i.e. if the memory can be allocated;
+ otherwise returns FALSE.
+
+ New elements are not initialized.
+
+ \sa size()
+*/
+
+/*!
+ \fn bool Q3MemArray::truncate( uint pos )
+
+ Truncates the array at position \a pos.
+
+ Returns TRUE if successful, i.e. if the memory can be allocated;
+ otherwise returns FALSE.
+
+ Equivalent to resize(\a pos).
+
+ \sa resize()
+*/
+
+/*!
+ \fn bool Q3MemArray::fill( const type &v, int size )
+
+ Fills the array with the value \a v. If \a size is specified as
+ different from -1, then the array will be resized before being
+ filled.
+
+ Returns TRUE if successful, i.e. if \a size is -1, or \a size is
+ != -1 and the memory can be allocated; otherwise returns FALSE.
+
+ \sa resize()
+*/
+
+/*!
+ \fn void Q3MemArray::detach()
+
+ Detaches this array from shared array data; i.e. it makes a
+ private, deep copy of the data.
+
+ Copying will be performed only if the \link nrefs() reference
+ count\endlink is greater than one.
+
+ \sa copy()
+*/
+
+/*!
+ \fn Q3MemArray<type> Q3MemArray::copy() const
+
+ Returns a deep copy of this array.
+
+ \sa detach(), duplicate()
+*/
+
+/*!
+ \fn Q3MemArray<type> &Q3MemArray::assign( const Q3MemArray<type> &a )
+
+ Shallow copy. Dereferences the current array and references the
+ data contained in \a a instead. Returns a reference to this array.
+
+ \sa operator=()
+*/
+
+/*!
+ \fn Q3MemArray<type> &Q3MemArray::assign( const type *data, uint size )
+
+ \overload
+
+ Shallow copy. Dereferences the current array and references the
+ array data \a data, which contains \a size elements. Returns a
+ reference to this array.
+
+ Do not delete \a data later; Q3MemArray will call free() on it
+ at the right time.
+*/
+
+/*!
+ \fn Q3MemArray<type> &Q3MemArray::duplicate( const Q3MemArray<type> &a )
+
+ Deep copy. Dereferences the current array and obtains a copy of
+ the data contained in \a a instead. Returns a reference to this
+ array.
+
+ \sa copy()
+*/
+
+/*!
+ \fn Q3MemArray<type> &Q3MemArray::duplicate( const type *data, uint size )
+
+ \overload
+
+ Deep copy. Dereferences the current array and obtains a copy of
+ the array data \a data instead. Returns a reference to this array.
+ The size of the array is given by \a size.
+
+ \sa copy()
+*/
+
+/*!
+ \fn Q3MemArray<type> &Q3MemArray::setRawData( const type *data, uint size )
+
+ Sets raw data and returns a reference to the array.
+
+ Dereferences the current array and sets the new array data to \a
+ data and the new array size to \a size. Do not attempt to resize
+ or re-assign the array data when raw data has been set. Call
+ resetRawData(\a data, \a size) to reset the array.
+
+ Setting raw data is useful because it sets Q3MemArray data without
+ allocating memory or copying data.
+
+ Example I (intended use):
+ \snippet doc/src/snippets/code/doc_src_q3memarray.qdoc 3
+
+ Example II (you don't want to do this):
+ \snippet doc/src/snippets/code/doc_src_q3memarray.qdoc 4
+
+ \warning If you do not call resetRawData(), Q3MemArray will attempt
+ to deallocate or reallocate the raw data, which might not be too
+ good. Be careful.
+
+ \sa resetRawData()
+*/
+
+/*!
+ \fn void Q3MemArray::resetRawData( const type *data, uint size )
+
+ Removes internal references to the raw data that was set using
+ setRawData(). This means that Q3MemArray no longer has access to
+ the \a data, so you are free to manipulate \a data as you wish.
+ You can now use the Q3MemArray without affecting the original \a
+ data, for example by calling setRawData() with a pointer to some
+ other data.
+
+ The arguments must be the \a data and length, \a size, that were
+ passed to setRawData(). This is for consistency checking.
+
+ \sa setRawData()
+*/
+
+/*!
+ \fn int Q3MemArray::find( const type &v, uint index ) const
+
+ Finds the first occurrence of \a v, starting at position \a index.
+
+ Returns the position of \a v, or -1 if \a v could not be found.
+
+ \sa contains()
+*/
+
+/*!
+ \fn int Q3MemArray::contains( const type &v ) const
+
+ Returns the number of times \a v occurs in the array.
+
+ \sa find()
+*/
+
+/*!
+ \fn void Q3MemArray::sort()
+
+ Sorts the array elements in ascending order, using bitwise
+ comparison (memcmp()).
+
+ \sa bsearch()
+*/
+
+/*!
+ \fn int Q3MemArray::bsearch( const type &v ) const
+
+ In a sorted array (as sorted by sort()), finds the first
+ occurrence of \a v by using a binary search. For a sorted
+ array this is generally much faster than find(), which does
+ a linear search.
+
+ Returns the position of \a v, or -1 if \a v could not be found.
+
+ \sa sort(), find()
+*/
+
+/*!
+ \fn type &Q3MemArray::operator[]( int index ) const
+
+ Returns a reference to the element at position \a index in the
+ array.
+
+ This can be used to both read and set an element. Equivalent to
+ at().
+
+ \sa at()
+*/
+
+/*!
+ \fn type &Q3MemArray::at( uint index ) const
+
+ Returns a reference to the element at position \a index in the array.
+
+ This can be used to both read and set an element.
+
+ \sa operator[]()
+*/
+
+/*!
+ \fn Q3MemArray::operator const type *() const
+
+ Cast operator. Returns a pointer to the array.
+
+ \sa data()
+*/
+
+/*!
+ \fn bool Q3MemArray::operator==( const Q3MemArray<type> &a ) const
+
+ Returns TRUE if this array is equal to \a a; otherwise returns
+ FALSE.
+
+ The two arrays are compared bitwise.
+
+ \sa operator!=()
+*/
+
+/*!
+ \fn bool Q3MemArray::operator!=( const Q3MemArray<type> &a ) const
+
+ Returns TRUE if this array is different from \a a; otherwise
+ returns FALSE.
+
+ The two arrays are compared bitwise.
+
+ \sa operator==()
+*/
+
+/*!
+ \fn Iterator Q3MemArray::begin()
+
+ Returns an iterator pointing at the beginning of this array. This
+ iterator can be used in the same way as the iterators of
+ Q3ValueList and QMap, for example.
+*/
+
+/*!
+ \fn Iterator Q3MemArray::end()
+
+ Returns an iterator pointing behind the last element of this
+ array. This iterator can be used in the same way as the iterators
+ of Q3ValueList and QMap, for example.
+*/
+
+/*!
+ \fn ConstIterator Q3MemArray::begin() const
+
+ \overload
+
+ Returns a const iterator pointing at the beginning of this array.
+ This iterator can be used in the same way as the iterators of
+ Q3ValueList and QMap, for example.
+*/
+
+/*!
+ \fn ConstIterator Q3MemArray::end() const
+
+ \overload
+
+ Returns a const iterator pointing behind the last element of this
+ array. This iterator can be used in the same way as the iterators
+ of Q3ValueList and QMap, for example.
+*/