macro_rules! error { (target: $target:expr, $($arg:tt)+) => { ... }; ($($arg:tt)+) => { ... }; }
Logs a message at the error level.
use log::error; let (err_info, port) = ("No connection", 22); error!("Error: {} on port {}", err_info, port); error!(target: "app_events", "App Error: {}, Port: {}", err_info, 22);