diff options
Diffstat (limited to 'doc/src/qvarlengtharray.qdoc')
| -rw-r--r-- | doc/src/qvarlengtharray.qdoc | 274 |
1 files changed, 0 insertions, 274 deletions
diff --git a/doc/src/qvarlengtharray.qdoc b/doc/src/qvarlengtharray.qdoc deleted file mode 100644 index 733cfa1..0000000 --- a/doc/src/qvarlengtharray.qdoc +++ /dev/null @@ -1,274 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). -** All rights reserved. -** Contact: Nokia Corporation (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 Technology Preview License Agreement accompanying -** this package. -** -** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package. -** -** If you have questions regarding the use of this file, please contact -** Nokia at qt-info@nokia.com. -** -** -** -** -** -** -** -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \class QVarLengthArray - \brief The QVarLengthArray class provides a low-level variable-length array. - - \ingroup tools - \reentrant - - The C++ language doesn't support variable-length arrays on the stack. - For example, the following code won't compile: - - \snippet doc/src/snippets/code/doc_src_qvarlengtharray.qdoc 0 - - The alternative is to allocate the array on the heap (with - \c{new}): - - \snippet doc/src/snippets/code/doc_src_qvarlengtharray.qdoc 1 - - However, if myfunc() is called very frequently from the - application's inner loop, heap allocation can be a major source - of slowdown. - - QVarLengthArray is an attempt to work around this gap in the C++ - language. It allocates a certain number of elements on the stack, - and if you resize the array to a larger size, it automatically - uses the heap instead. Stack allocation has the advantage that - it is much faster than heap allocation. - - Example: - \snippet doc/src/snippets/code/doc_src_qvarlengtharray.qdoc 2 - - In the example above, QVarLengthArray will preallocate 1024 - elements on the stack and use them unless \c{n + 1} is greater - than 1024. If you omit the second template argument, - QVarLengthArray's default of 256 is used. - - QVarLengthArray's value type must be an \l{assignable data type}. - This covers most data types that are commonly used, but the - compiler won't let you, for example, store a QWidget as a value; - instead, store a QWidget *. - - QVarLengthArray, like QVector, provides a resizable array data - structure. The main differences between the two classes are: - - \list - \o QVarLengthArray's API is much more low-level. It provides no - iterators and lacks much of QVector's functionality. - - \o QVarLengthArray doesn't initialize the memory if the value is - a basic type. (QVector always does.) - - \o QVector uses \l{implicit sharing} as a memory optimization. - QVarLengthArray doesn't provide that feature; however, it - usually produces slightly better performance due to reduced - overhead, especially in tight loops. - \endlist - - In summary, QVarLengthArray is a low-level optimization class - that only makes sense in very specific cases. It is used a few - places inside Qt and was added to Qt's public API for the - convenience of advanced users. - - \sa QVector, QList, QLinkedList -*/ - -/*! \fn QVarLengthArray::QVarLengthArray(int size) - - Constructs an array with an initial size of \a size elements. - - If the value type is a primitive type (e.g., char, int, float) or - a pointer type (e.g., QWidget *), the elements are not - initialized. For other types, the elements are initialized with a - \l{default-constructed value}. -*/ - -/*! \fn QVarLengthArray::~QVarLengthArray() - - Destroys the array. -*/ - -/*! \fn int QVarLengthArray::size() const - - Returns the number of elements in the array. - - \sa isEmpty(), resize() -*/ - -/*! \fn int QVarLengthArray::count() const - - Same as size(). - - \sa isEmpty(), resize() -*/ - -/*! \fn bool QVarLengthArray::isEmpty() const - - Returns true if the array has size 0; otherwise returns false. - - \sa size(), resize() -*/ - -/*! \fn void QVarLengthArray::clear() - - Removes all the elements from the array. - - Same as resize(0). -*/ - -/*! \fn void QVarLengthArray::resize(int size) - - Sets the size of the array to \a size. If \a size is greater than - the current size, elements are added to the end. If \a size is - less than the current size, elements are removed from the end. - - If the value type is a primitive type (e.g., char, int, float) or - a pointer type (e.g., QWidget *), new elements are not - initialized. For other types, the elements are initialized with a - \l{default-constructed value}. - - \sa size() -*/ - -/*! \fn int QVarLengthArray::capacity() const - - Returns the maximum number of elements that can be stored in the - array without forcing a reallocation. - - The sole purpose of this function is to provide a means of fine - tuning QVarLengthArray's memory usage. In general, you will rarely ever - need to call this function. If you want to know how many items are - in the array, call size(). - - \sa reserve() -*/ - -/*! \fn void QVarLengthArray::reserve(int size) - - Attempts to allocate memory for at least \a size elements. If you - know in advance how large the array can get, you can call this - function and if you call resize() often, you are likely to get - better performance. If \a size is an underestimate, the worst - that will happen is that the QVarLengthArray will be a bit - slower. - - The sole purpose of this function is to provide a means of fine - tuning QVarLengthArray's memory usage. In general, you will - rarely ever need to call this function. If you want to change the - size of the array, call resize(). - - \sa capacity() -*/ - -/*! \fn T &QVarLengthArray::operator[](int i) - - Returns a reference to the item at index position \a i. - - \a i must be a valid index position in the array (i.e., 0 <= \a i - < size()). - - \sa data() -*/ - -/*! \fn const T &QVarLengthArray::operator[](int i) const - - \overload -*/ - - -/*! - \fn void QVarLengthArray::append(const T &t) - - Appends item \a t to the array, extending the array if necessary. - - \sa removeLast() -*/ - - -/*! - \fn inline void QVarLengthArray::removeLast() - \since 4.5 - - Decreases the size of the array by one. The allocated size is not changed. - - \sa append() -*/ - -/*! - \fn void QVarLengthArray::append(const T *buf, int size) - - Appends \a size amount of items referenced by \a buf to this array. -*/ - - -/*! \fn T *QVarLengthArray::data() - - Returns a pointer to the data stored in the array. The pointer can - be used to access and modify the items in the array. - - Example: - \snippet doc/src/snippets/code/doc_src_qvarlengtharray.qdoc 3 - - The pointer remains valid as long as the array isn't reallocated. - - This function is mostly useful to pass an array to a function - that accepts a plain C++ array. - - \sa constData(), operator[]() -*/ - -/*! \fn const T *QVarLengthArray::data() const - - \overload -*/ - -/*! \fn const T *QVarLengthArray::constData() const - - Returns a const pointer to the data stored in the array. The - pointer can be used to access the items in the array. The - pointer remains valid as long as the array isn't reallocated. - - This function is mostly useful to pass an array to a function - that accepts a plain C++ array. - - \sa data(), operator[]() -*/ - -/*! \fn QVarLengthArray<T, Prealloc> &QVarLengthArray::operator=(const QVarLengthArray<T, Prealloc> &other) - Assigns \a other to this array and returns a reference to this array. - */ - -/*! \fn QVarLengthArray::QVarLengthArray(const QVarLengthArray<T, Prealloc> &other) - Constructs a copy of \a other. - */ - |