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+// Copyright (C) 2021 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
+
+/*!
+\page qt-extract-metatypes.html
+\ingroup cmake-commands-qtcore
+
+\title qt_extract_metatypes
+\keyword qt6_extract_metatypes
+
+\summary {Extracts metatypes from a Qt target and generates an associated metatypes.json file.}
+
+\cmakecommandsince 6.0
+\preliminarycmakecommand
+
+\section1 Synopsis
+
+\badcode
+qt_extract_metatypes(target
+    [MANUAL_MOC_JSON_FILES json_files...]
+    [OUTPUT_FILES variable_name]
+)
+\endcode
+
+\versionlessCMakeCommandsNote qt6_extract_metatypes()
+
+\section1 Description
+
+Certain operations rely on metatype information being generated and collected
+on targets. This is typically handled internally by Qt commands, but for
+scenarios where this is not the case, \c{qt_extract_metatypes()} can be called
+to force the collection of this information for a specific \c target.
+
+Metatype information is generated for a target's source files in one of the
+following ways:
+
+\list
+\li Automatically by AUTOMOC. The \c{qt_extract_metatypes()} command detects
+    when AUTOMOC is enabled on the \c target and will automatically extract the
+    information it needs.
+\li Manually by invoking \c moc with the \c{--output-json} option. The project
+    is responsible for keeping track of all the JSON files generated using this
+    method and passing them to \c{qt_extract_metatypes()} with the
+    \c MANUAL_MOC_JSON_FILES option.
+\endlist
+
+\c{qt_extract_metatypes()} produces a target-specific metatypes JSON file which
+collects all the metatype details from the AUTOMOC and manual moc inputs.
+It does this by calling \c moc with the \c{--collect-json} option.
+If you need to know where to find the resultant metatypes JSON file (for
+example, to pass it to another command or to install it), use the
+\c OUTPUT_FILES option to provide the name of a variable in which to store its
+absolute path.
+
+\section1 Automatic metatype extraction
+
+Since Qt 6.8, if you have not disabled \c{AUTOMOC} and either are using CMake
+3.19 or later or are calling \l{qt6_finalize_target}{qt_finalize_target()}
+manually, then \c{qt_extract_metatypes()} is automatically called as part of the
+finalization step for \l{qt_add_library}. This has no effect if you have
+manually called \c{qt_extract_metatypes()} before the finalization, possibly
+with custom arguments. However, it does make sure that the metatypes are also
+produced if you haven't. This is important if any of the types in the library
+are used as part of any QML types any time in the future and has no downsides.
+
+Furthermore, \l{qt_add_qml_module} automatically invokes
+\c{qt_extract_metatypes()} for its target.
+
+*/