# uselog_rs before using `uselog_rs`, you must use four lines code to use log for outputing log in `test mode` and `not test mode` ``` #[cfg(not(test))] use log::{debug, info, warn}; #[cfg(test)] use std::{println as debug, println as info, println as warn}; ``` now just one line code ``` uselog!(debug, info, warn) ``` but you need to add `uselog_rs` to your parent module first like ``` #[macro_use(uselog)] extern crate uselog_rs; ```