// Copyright 2014-2015 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. /// The standard logging macro. /// /// This macro will generically log with the specified `Level` and `format!` /// based argument list. /// /// # Examples /// /// ```edition2018 /// use log::{log, Level}; /// /// # fn main() { /// let data = (42, "Forty-two"); /// let private_data = "private"; /// /// log!(Level::Error, "Received errors: {}, {}", data.0, data.1); /// log!(target: "app_events", Level::Warn, "App warning: {}, {}, {}", /// data.0, data.1, private_data); /// # } /// ``` #[macro_export(local_inner_macros)] macro_rules! log { (target: $target:expr, $lvl:expr, $($arg:tt)+) => ({ let lvl = $lvl; if lvl <= $crate::STATIC_MAX_LEVEL && lvl <= $crate::max_level() { $crate::__private_api_log( __log_format_args!($($arg)+), lvl, &($target, __log_module_path!(), __log_file!(), __log_line!()), ); } }); ($lvl:expr, $($arg:tt)+) => (log!(target: __log_module_path!(), $lvl, $($arg)+)) } /// Logs a message at the error level. /// /// # Examples /// /// ```edition2018 /// use log::error; /// /// # fn main() { /// let (err_info, port) = ("No connection", 22); /// /// error!("Error: {} on port {}", err_info, port); /// error!(target: "app_events", "App Error: {}, Port: {}", err_info, 22); /// # } /// ``` #[macro_export(local_inner_macros)] macro_rules! error { (target: $target:expr, $($arg:tt)+) => ( log!(target: $target, $crate::Level::Error, $($arg)+) ); ($($arg:tt)+) => ( log!($crate::Level::Error, $($arg)+) ) } /// Logs a message at the warn level. /// /// # Examples /// /// ```edition2018 /// use log::warn; /// /// # fn main() { /// let warn_description = "Invalid Input"; /// /// warn!("Warning! {}!", warn_description); /// warn!(target: "input_events", "App received warning: {}", warn_description); /// # } /// ``` #[macro_export(local_inner_macros)] macro_rules! warn { (target: $target:expr, $($arg:tt)+) => ( log!(target: $target, $crate::Level::Warn, $($arg)+) ); ($($arg:tt)+) => ( log!($crate::Level::Warn, $($arg)+) ) } /// Logs a message at the info level. /// /// # Examples /// /// ```edition2018 /// use log::info; /// /// # fn main() { /// # struct Connection { port: u32, speed: f32 } /// let conn_info = Connection { port: 40, speed: 3.20 }; /// /// info!("Connected to port {} at {} Mb/s", conn_info.port, conn_info.speed); /// info!(target: "connection_events", "Successfull connection, port: {}, speed: {}", /// conn_info.port, conn_info.speed); /// # } /// ``` #[macro_export(local_inner_macros)] macro_rules! info { (target: $target:expr, $($arg:tt)+) => ( log!(target: $target, $crate::Level::Info, $($arg)+) ); ($($arg:tt)+) => ( log!($crate::Level::Info, $($arg)+) ) } /// Logs a message at the debug level. /// /// # Examples /// /// ```edition2018 /// use log::debug; /// /// # fn main() { /// # struct Position { x: f32, y: f32 } /// let pos = Position { x: 3.234, y: -1.223 }; /// /// debug!("New position: x: {}, y: {}", pos.x, pos.y); /// debug!(target: "app_events", "New position: x: {}, y: {}", pos.x, pos.y); /// # } /// ``` #[macro_export(local_inner_macros)] macro_rules! debug { (target: $target:expr, $($arg:tt)+) => ( log!(target: $target, $crate::Level::Debug, $($arg)+) ); ($($arg:tt)+) => ( log!($crate::Level::Debug, $($arg)+) ) } /// Logs a message at the trace level. /// /// # Examples /// /// ```edition2018 /// use log::trace; /// /// # fn main() { /// # struct Position { x: f32, y: f32 } /// let pos = Position { x: 3.234, y: -1.223 }; /// /// trace!("Position is: x: {}, y: {}", pos.x, pos.y); /// trace!(target: "app_events", "x is {} and y is {}", /// if pos.x >= 0.0 { "positive" } else { "negative" }, /// if pos.y >= 0.0 { "positive" } else { "negative" }); /// # } /// ``` #[macro_export(local_inner_macros)] macro_rules! trace { (target: $target:expr, $($arg:tt)+) => ( log!(target: $target, $crate::Level::Trace, $($arg)+) ); ($($arg:tt)+) => ( log!($crate::Level::Trace, $($arg)+) ) } /// Determines if a message logged at the specified level in that module will /// be logged. /// /// This can be used to avoid expensive computation of log message arguments if /// the message would be ignored anyway. /// /// # Examples /// /// ```edition2018 /// use log::Level::Debug; /// use log::{debug, log_enabled}; /// /// # fn foo() { /// if log_enabled!(Debug) { /// let data = expensive_call(); /// debug!("expensive debug data: {} {}", data.x, data.y); /// } /// if log_enabled!(target: "Global", Debug) { /// let data = expensive_call(); /// debug!(target: "Global", "expensive debug data: {} {}", data.x, data.y); /// } /// # } /// # struct Data { x: u32, y: u32 } /// # fn expensive_call() -> Data { Data { x: 0, y: 0 } } /// # fn main() {} /// ``` #[macro_export(local_inner_macros)] macro_rules! log_enabled { (target: $target:expr, $lvl:expr) => {{ let lvl = $lvl; lvl <= $crate::STATIC_MAX_LEVEL && lvl <= $crate::max_level() && $crate::__private_api_enabled(lvl, $target) }}; ($lvl:expr) => { log_enabled!(target: __log_module_path!(), $lvl) }; } // The log macro above cannot invoke format_args directly because it uses // local_inner_macros. A format_args invocation there would resolve to // $crate::format_args which does not exist. Instead invoke format_args here // outside of local_inner_macros so that it resolves (probably) to // core::format_args or std::format_args. Same for the several macros that // follow. // // This is a workaround until we drop support for pre-1.30 compilers. At that // point we can remove use of local_inner_macros, use $crate:: when invoking // local macros, and invoke format_args directly. #[doc(hidden)] #[macro_export] macro_rules! __log_format_args { ($($args:tt)*) => { format_args!($($args)*) }; } #[doc(hidden)] #[macro_export] macro_rules! __log_module_path { () => { module_path!() }; } #[doc(hidden)] #[macro_export] macro_rules! __log_file { () => { file!() }; } #[doc(hidden)] #[macro_export] macro_rules! __log_line { () => { line!() }; }