cmake HAVE_STD_EXECUTION_H examples

jstkdng/ueberzugpp CMakeLists.txt :52 

check_cxx_symbol_exists(std::execution::par_unseq execution
                        HAVE_STD_EXECUTION_H)

jstkdng/ueberzugpp CMakeLists.txt :55 

target_compile_definitions(ueberzug PRIVATE HAVE_STD_EXECUTION_H)