_IS_TOP_LEVEL

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Cmake/docs/3.21/variable/project-name is top level


_IS_TOP_LEVEL

New in version 3.21.


A boolean variable indicating whether the named project was called in a top level CMakeLists.txt file.

To obtain the value from the most recent call to project() in the current directory scope or above, see the PROJECT_IS_TOP_LEVEL variable.

The variable value will be true in:

  • the top-level directory of the project
  • the top-level directory of an external project added by ExternalProject

The variable value will be false in:

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https://cmake.org/cmake/help/v3.21/variable/PROJECT-NAME_IS_TOP_LEVEL.html