include(ExternalProject) project(better-enums) ExternalProject_Add(${PROJECT_NAME}-external GIT_REPOSITORY https://github.com/aantron/better-enums.git GIT_TAG "0.11.3" GIT_SHALLOW TRUE SOURCE_DIR ${THIRD_PARTY_DIR}/${PROJECT_NAME} BUILD_COMMAND "" INSTALL_COMMAND "" CONFIGURE_COMMAND "") add_library(${PROJECT_NAME} INTERFACE) add_dependencies(${PROJECT_NAME} ${PROJECT_NAME}-external) target_include_directories(${PROJECT_NAME} SYSTEM INTERFACE ${THIRD_PARTY_DIR}/${PROJECT_NAME})