qt_policy.qdoc

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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
/*!
\page qt-policy.html
\ingroup cmake-commands-qtcore
 
\title qt_policy
\keyword qt6_policy
 
\summary {Modify the default behavior of Qt's CMake API.}
 
\include cmake-find-package-core.qdocinc
 
\cmakecommandsince 6.5
 
\section1 Synopsis
 
\badcode
qt_policy(
    [SET <policy_name> behavior]
    [GET <policy_name> <variable>]
)
\endcode
 
\versionlessCMakeCommandsNote qt6_policy()
 
\section1 Description
 
This command has two modes:
 
\list
\li When the \c{SET} keyword is used, this command can be used to opt in to
    behavior changes in Qt's CMake API, or to explicitly opt out of them.
\li When the \c{GET} keyword is used, \c{<variable>} is set to the current
    behavior for the policy, i.e. \c OLD or \c NEW.
\endlist
 
\c{<policy_name>} must be the name of one of the \l{Qt CMake policies}.
Policy names have the form of \c{QTP<NNNN>} where <NNNN> is
an integer specifying the index of the policy. Using an invalid policy
name results in an error.
 
Code supporting older Qt versions can check the existence of a policy by
checking the value of the \c{QT_KNOWN_POLICY_<policy_name>} variable before
getting the value of \c <policy_name> or setting its behavior.
 
\badcode
if(QT_KNOWN_POLICY_<policy_name>)
    qt_policy(SET <policy_name> NEW)
endif()
\endcode
 
You can set \c behavior to one of the following options:
 
\list
\li \c{NEW} to opt into the new behavior
\li \c{OLD} to explicitly opt-out of it
\endlist
 
\qtpolicydeprecatedbehavior
 
\sa qt_standard_project_setup
 
*/