include(FetchContent) FetchContent_Declare( ctre GIT_REPOSITORY "https://github.com/hanickadot/compile-time-regular-expressions" GIT_TAG v3.5 ) add_subdirectory(ctre) FetchContent_Declare( fmt GIT_REPOSITORY "https://github.com/fmtlib/fmt" GIT_TAG 8.1.1 ) add_subdirectory(fmt) FetchContent_Declare( GSL GIT_REPOSITORY "https://github.com/Microsoft/GSL" GIT_TAG v4.0.0 ) add_subdirectory(GSL) FetchContent_Declare( doctest GIT_REPOSITORY "https://github.com/doctest/doctest" GIT_TAG v2.4.8 ) add_subdirectory(doctest)