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/*!
    \page qtconcurrent-index.html
    \title Qt Concurrent

    \brief The Qt Concurrent module contains functionality to support concurrent execution of program code.

    \section1 Getting Started

    The QtConcurrent namespace provides high-level APIs that make it
    possible to write multi-threaded programs without using low-level
    threading primitives such as mutexes, read-write locks, wait
    conditions, or semaphores. Programs written with QtConcurrent
    automatically adjust the number of threads used according to the
    number of processor cores available. This means that applications
    written today will continue to scale when deployed on multi-core
    systems in the future.

    QtConcurrent includes functional programming style APIs for
    parallel list processing, including a MapReduce and FilterReduce
    implementation for shared-memory (non-distributed) systems, and
    classes for managing asynchronous computations in GUI
    applications:

    \list

    \li QtConcurrent::map() applies a function to every item in a container,
    modifying the items in-place.

    \li QtConcurrent::mapped() is like map(), except that it returns a new
    container with the modifications.

    \li QtConcurrent::mappedReduced() is like mapped(), except that the
    modified results are reduced or folded into a single result.

    \li QtConcurrent::filter() removes all items from a container based on the
    result of a filter function.

    \li QtConcurrent::filtered() is like filter(), except that it returns a new
    container with the filtered results.

    \li QtConcurrent::filteredReduced() is like filtered(), except that the
    filtered results are reduced or folded into a single result.

    \li QtConcurrent::run() runs a function in another thread.

    \li QFuture represents the result of an asynchronous computation.

    \li QFutureIterator allows iterating through results available via QFuture.

    \li QFutureWatcher allows monitoring a QFuture using signals-and-slots.

    \li QFutureSynchronizer is a convenience class that automatically
    synchronizes several QFutures.

    \endlist

    Qt Concurrent supports several STL-compatible container and iterator types,
    but works best with Qt containers that have random-access iterators, such as
    QList or QVector. The map and filter functions accept both containers and begin/end iterators.

    STL Iterator support overview:

    \table
    \header
        \li Iterator Type
        \li Example classes
        \li Support status
    \row
        \li Input Iterator
        \li
        \li Not Supported
    \row
        \li Output Iterator
        \li
        \li Not Supported
    \row
        \li Forward Iterator
        \li std::slist
        \li Supported
    \row
        \li Bidirectional Iterator
        \li QLinkedList, std::list
        \li Supported
    \row
        \li Random Access Iterator
        \li QList, QVector, std::vector
        \li Supported and Recommended
    \endtable

    Random access iterators can be faster in cases where Qt Concurrent is iterating
    over a large number of lightweight items, since they allow skipping to any point
    in the container. In addition, using random access iterators allows Qt Concurrent
    to provide progress information trough QFuture::progressValue() and QFutureWatcher::
    progressValueChanged().

    The non in-place modifying functions such as mapped() and filtered() makes a
    copy of the container when called. If you are using STL containers this copy operation
    might take some time, in this case we recommend specifying the begin and end iterators
    for the container instead.
*/