_VERSION

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Cmake/docs/3.21/variable/project-name version


_VERSION

Value given to the VERSION option of the most recent call to the project() command with project name <PROJECT-NAME>, if any.

See also the component-wise version variables _VERSION_MAJOR, _VERSION_MINOR, _VERSION_PATCH, and _VERSION_TWEAK.

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Licensed under the BSD 3-clause License.
https://cmake.org/cmake/help/v3.21/variable/PROJECT-NAME_VERSION.html