-ifdef('21.0'). -define(WITH_STACKTRACE(T, R, S), T:R:S ->). -else. -define(WITH_STACKTRACE(T, R, S), T:R -> S = erlang:get_stacktrace(),). -endif. -ifdef('21.0'). -include_lib("kernel/include/logger.hrl"). -else. -define(LOG_INFO(Format, Args), error_logger:info_msg(Format, Args)). -define(LOG_ERROR(Format, Args), error_logger:error_msg(Format, Args)). -endif.