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/*****************************************************************************
  QMemArray documentation
 *****************************************************************************/

/*!
  \class QMemArray qmemarray.h
  \brief The QMemArray class is a template class that provides arrays of simple types.

  \ingroup tools

  QMemArray is implemented as a template class. Define a template
  instance QMemArray\<X\> to create an array that contains X items.

  QMemArray stores the array elements directly in the array. It can
  deal only with simple types (i.e. C++ types, structs, and classes that have
  no constructors, destructors, or virtual functions).  QMemArray uses
  bitwise operations to copy and compare array elements.

  The QPtrVector collection class is also a kind of array.  Like most
  \link collection.html collection classes\endlink, it has pointers to the
  contained items.

  QMemArray uses explicit \link shclass.html sharing\endlink with a reference
  count.  If more than one array share common data and one array is
  modified, all arrays will be modified.

  The benefit of sharing is that a program does not need to duplicate
  data when it is not required, which results in less memory usage and
  less copying of data.

  Example:
  \code
    #include <qmemarray.h>
    #include <stdio.h>

    QMemArray<int> fib( int num ) // returns fibonacci array
    {
	Q_ASSERT( num > 2 );
	QMemArray<int> f( num ); // array of ints

	f[0] = f[1] = 1;
	for ( int i = 2; i < num; i++ )
	    f[i] = f[i-1] + f[i-2];

	return f;
    }

    int main()
    {
	QMemArray<int> a = fib( 6 ); // get 6 first fibonaccis
	for ( int i = 0; i < a.size(); i++ )
	    qDebug( "%d: %d", i, a[i] );

	qDebug( "1 is found %d times", a.contains(1) );
	qDebug( "5 is found at index %d", a.find(5) );

	return 0;
    }
  \endcode

  Program output:
  \code
    0: 1
    1: 1
    2: 2
    3: 3
    4: 5
    5: 8
    1 is found 2 times
    5 is found at index 4
  \endcode

  Note about using QMemArray 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 QMemArray 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:

  \code
    // MyStruct may be padded to 4 or 8 bytes
    struct MyStruct
    {
	short i; // 2 bytes
	char c;  // 1 byte
    };

    QMemArray<MyStruct> a(1);
    a[0].i = 5;
    a[0].c = 't';

    MyStruct x;
    x.i = '5';
    x.c = 't';
    int i = a.find( x ); // may return -1 if the pad bytes differ
  \endcode

  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.

  QMemArray 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.

  \sa \link shclass.html Shared Classes\endlink
*/

/*! \enum QMemArray::Iterator
    A QMemArray iterator.
    \sa begin() end()
*/
/*! \enum QMemArray::ConstIterator
    A const QMemArray iterator.
    \sa begin() end()
*/
/*! \enum QMemArray::ValueType
    \internal
*/

/*!
  \fn QMemArray::QMemArray()
  Constructs a null array.
  \sa isNull()
*/

/*!
  \fn QMemArray::QMemArray( 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 QMemArray::QMemArray( const QMemArray<type> &a )
  Constructs a shallow copy of \a a.
  \sa assign()
*/

/*!
  \fn QMemArray::QMemArray( int, int )
  Constructs an array \e {without allocating} array space.
  The arguments should be (0, 0). Use at your own risk.
*/

/*!
  \fn QMemArray::~QMemArray()
  Dereferences the array data and deletes it if this was the last
  reference.
*/

/*!
  \fn QMemArray<type> &QMemArray::operator=( const QMemArray<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 *QMemArray::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 QMemArray::nrefs() const
  Returns the reference count for the shared array data. This reference count
  is always greater than zero.
*/

/*!
  \fn uint QMemArray::size() const
  Returns the size of the array (max number of elements).

  The array is a null array if size() == 0.

  \sa isNull(), resize()
*/

/*!
  \fn uint QMemArray::count() const
  Returns the same as size().

  \sa size()
*/

/*!
  \fn bool QMemArray::isEmpty() const
  Returns TRUE if the array is empty; otherwise returns FALSE.

  isEmpty() is equivalent to isNull() for QMemArray (unlike QString).
*/

/*!
  \fn bool QMemArray::isNull() const

  Returns TRUE if the array is null; otherwise returns FALSE.

  A null array has size() == 0 and data() == 0.
*/

/*!
  \fn bool QMemArray::resize( uint size )

  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 will not be initialized.

  \sa size()
*/

/*!
  \fn bool QMemArray::truncate( uint pos )

  Truncates the array at position \a pos.

  Returns TRUE if successful, or FALSE if the memory cannot be allocated.

  Equivalent to resize(\a pos).

  \sa resize()
*/

/*!
  \fn bool QMemArray::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, or FALSE if the memory cannot be allocated
  (only when \a size != -1).

  \sa resize()
*/

/*!
  \fn void QMemArray::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 QMemArray<type> QMemArray::copy() const
  Returns a deep copy of this array.
  \sa detach(), duplicate()
*/

/*!
  \fn QMemArray<type> &QMemArray::assign( const QMemArray<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 QMemArray<type> &QMemArray::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; QMemArray will take care of it.
*/

/*!
  \fn QMemArray<type> &QMemArray::duplicate( const QMemArray<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 QMemArray<type> &QMemArray::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 QMemArray<type> &QMemArray::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 QMemArray data without allocating
  memory or copying data.

  Example I (intended use):
  \code
    static char bindata[] = { 231, 1, 44, ... };
    QByteArray	a;
    a.setRawData( bindata, sizeof(bindata) );	// a points to bindata
    QDataStream s( a, IO_ReadOnly );		// open on a's data
    s >> <something>;				// read raw bindata
    a.resetRawData( bindata, sizeof(bindata) ); // finished
  \endcode

  Example II (you don't want to do this):
  \code
    static char bindata[] = { 231, 1, 44, ... };
    QByteArray	a, b;
    a.setRawData( bindata, sizeof(bindata) );	// a points to bindata
    a.resize( 8 );				// will crash
    b = a;					// will crash
    a[2] = 123;					// might crash
    // forget to resetRawData: will crash
  \endcode

  \warning If you do not call resetRawData(), QMemArray will attempt to
  deallocate or reallocate the raw data, which might not be too good.
  Be careful.

  \sa resetRawData()
*/

/*!
  \fn void QMemArray::resetRawData( const type *data, uint size )
  Resets raw data that was set using setRawData().

  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 QMemArray::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 QMemArray::contains( const type &v ) const
  Returns the number of times \a v occurs in the array.
  \sa find()
*/

/*!
  \fn void QMemArray::sort()
  Sorts the array elements in ascending order, using bitwise
  comparison (memcmp()).

  \sa bsearch()
*/

/*!
  \fn int QMemArray::bsearch( const type &v ) const
  In a sorted array, finds the first occurrence of \a v by using 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 &QMemArray::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 &QMemArray::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 QMemArray::operator const type *() const
  Cast operator.  Returns a pointer to the array.
  \sa data()
*/

/*!
  \fn bool QMemArray::operator==( const QMemArray<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 QMemArray::operator!=( const QMemArray<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 QMemArray::begin()
  Returns an iterator pointing at the beginning of this array.
  This iterator can be used in the same way as the iterators of
  QValueList and QMap, for example. In fact, not only does it behave
  like a usual pointer, it is a pointer.
*/

/*!
  \fn Iterator QMemArray::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
  QValueList and QMap, for example. In fact, not only does it behave
  like a usual pointer, it is a pointer.
*/

/*!
  \overload ConstIterator QMemArray::begin() const
  Returns a const iterator pointing at the beginning of this array.
  This iterator can be used in the same way as the iterators of
  QValueList and QMap, for example. In fact, not only does it behave
  like a usual pointer, it is a pointer.
*/

/*!
  \overload ConstIterator QMemArray::end() const
  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
  QValueList and QMap, for example. In fact, not only does it behave
  like a usual pointer, it is a pointer.
*/