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/****************************************************************************
**
** Copyright (C) 2020 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of The Qt Company Ltd nor the names of its
** contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
//! [0]
QtConcurrent::task([]{ qDebug("Hello, world!"); }).spawn();
//! [0]
//! [1]
auto task = [](const QString &s){ qDebug() << ("Hello, " + s); };
QtConcurrent::task(std::move(task))
.withArguments("world!")
.spawn();
//! [1]
//! [2]
QString s("Hello, ");
QtConcurrent::task([](QString &s){ s.append("world!"); })
.withArguments(std::ref(s))
.spawn();
//! [2]
//! [3]
auto future = QtConcurrent::task([]{ return 42; }).spawn();
auto result = future.result(); // result == 42
//! [3]
//! [4]
std::is_invocable_v<std::decay_t<Task>, std::decay_t<Args>...>
//! [4]
//! [5]
QVariant value(42);
auto result = QtConcurrent::task(&qvariant_cast<int>)
.withArguments(value)
.spawn()
.result(); // result == 42
//! [5]
//! [6]
QString result("Hello, world!");
QtConcurrent::task(&QString::chop)
.withArguments(&result, 8)
.spawn()
.waitForFinished(); // result == "Hello"
//! [6]
//! [7]
auto result = QtConcurrent::task(std::plus<int>())
.withArguments(40, 2)
.spawn()
.result() // result == 42
//! [7]
//! [8]
struct CallableWithState
{
void operator()(int newState) { state = newState; }
// ...
};
// ...
CallableWithState object;
QtConcurrent::task(std::ref(object))
.withArguments(42)
.spawn()
.waitForFinished(); // The object's state is set to 42
//! [8]
//! [9]
QThreadPool pool;
QtConcurrent::task([]{ return 42; }).onThreadPool(pool).spawn();
//! [9]
//! [10]
QtConcurrent::task([]{ return 42; }).withPriority(10).spawn();
//! [10]
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