// 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 /// /// ``` /// 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] macro_rules! log { // log!(target: "my_target", Level::Info, key1:? = 42, key2 = true; "a {} event", "log"); (target: $target:expr, $lvl:expr, $($key:tt $(:$capture:tt)? $(= $value:expr)?),+; $($arg:tt)+) => ({ let lvl = $lvl; if lvl <= $crate::STATIC_MAX_LEVEL && lvl <= $crate::max_level() { $crate::__private_api::log::<&_>( $crate::__private_api::format_args!($($arg)+), lvl, &($target, $crate::__private_api::module_path!(), $crate::__private_api::loc()), &[$(($crate::__log_key!($key), $crate::__log_value!($key $(:$capture)* = $($value)*))),+] ); } }); // log!(target: "my_target", Level::Info, "a {} event", "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( $crate::__private_api::format_args!($($arg)+), lvl, &($target, $crate::__private_api::module_path!(), $crate::__private_api::loc()), (), ); } }); // log!(Level::Info, "a log event") ($lvl:expr, $($arg:tt)+) => ($crate::log!(target: $crate::__private_api::module_path!(), $lvl, $($arg)+)); } /// Logs a message at the error level. /// /// # Examples /// /// ``` /// use log::error; /// /// # fn main() { /// let (err_info, port) = ("No connection", 22); /// /// error!("Error: {err_info} on port {port}"); /// error!(target: "app_events", "App Error: {err_info}, Port: {port}"); /// # } /// ``` #[macro_export] macro_rules! error { // error!(target: "my_target", key1 = 42, key2 = true; "a {} event", "log") // error!(target: "my_target", "a {} event", "log") (target: $target:expr, $($arg:tt)+) => ($crate::log!(target: $target, $crate::Level::Error, $($arg)+)); // error!("a {} event", "log") ($($arg:tt)+) => ($crate::log!($crate::Level::Error, $($arg)+)) } /// Logs a message at the warn level. /// /// # Examples /// /// ``` /// 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] macro_rules! warn { // warn!(target: "my_target", key1 = 42, key2 = true; "a {} event", "log") // warn!(target: "my_target", "a {} event", "log") (target: $target:expr, $($arg:tt)+) => ($crate::log!(target: $target, $crate::Level::Warn, $($arg)+)); // warn!("a {} event", "log") ($($arg:tt)+) => ($crate::log!($crate::Level::Warn, $($arg)+)) } /// Logs a message at the info level. /// /// # Examples /// /// ``` /// 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", "Successful connection, port: {}, speed: {}", /// conn_info.port, conn_info.speed); /// # } /// ``` #[macro_export] macro_rules! info { // info!(target: "my_target", key1 = 42, key2 = true; "a {} event", "log") // info!(target: "my_target", "a {} event", "log") (target: $target:expr, $($arg:tt)+) => ($crate::log!(target: $target, $crate::Level::Info, $($arg)+)); // info!("a {} event", "log") ($($arg:tt)+) => ($crate::log!($crate::Level::Info, $($arg)+)) } /// Logs a message at the debug level. /// /// # Examples /// /// ``` /// 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] macro_rules! debug { // debug!(target: "my_target", key1 = 42, key2 = true; "a {} event", "log") // debug!(target: "my_target", "a {} event", "log") (target: $target:expr, $($arg:tt)+) => ($crate::log!(target: $target, $crate::Level::Debug, $($arg)+)); // debug!("a {} event", "log") ($($arg:tt)+) => ($crate::log!($crate::Level::Debug, $($arg)+)) } /// Logs a message at the trace level. /// /// # Examples /// /// ``` /// 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] macro_rules! trace { // trace!(target: "my_target", key1 = 42, key2 = true; "a {} event", "log") // trace!(target: "my_target", "a {} event", "log") (target: $target:expr, $($arg:tt)+) => ($crate::log!(target: $target, $crate::Level::Trace, $($arg)+)); // trace!("a {} event", "log") ($($arg:tt)+) => ($crate::log!($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 /// /// ``` /// 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] 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) => { $crate::log_enabled!(target: $crate::__private_api::module_path!(), $lvl) }; } // These macros use a pattern of #[cfg]s to produce nicer error // messages when log features aren't available #[doc(hidden)] #[macro_export] #[cfg(feature = "kv")] macro_rules! __log_key { // key1 = 42 ($($args:ident)*) => { $crate::__private_api::stringify!($($args)*) }; // "key1" = 42 ($($args:expr)*) => { $($args)* }; } #[doc(hidden)] #[macro_export] #[cfg(not(feature = "kv"))] macro_rules! __log_key { ($($args:tt)*) => { compile_error!("key value support requires the `kv` feature of `log`") }; } #[doc(hidden)] #[macro_export] #[cfg(feature = "kv")] macro_rules! __log_value { // Entrypoint ($key:tt = $args:expr) => { $crate::__log_value!(($args):value) }; ($key:tt :$capture:tt = $args:expr) => { $crate::__log_value!(($args):$capture) }; ($key:ident =) => { $crate::__log_value!(($key):value) }; ($key:ident :$capture:tt =) => { $crate::__log_value!(($key):$capture) }; // ToValue (($args:expr):value) => { $crate::__private_api::capture_to_value(&&$args) }; // Debug (($args:expr):?) => { $crate::__private_api::capture_debug(&&$args) }; (($args:expr):debug) => { $crate::__private_api::capture_debug(&&$args) }; // Display (($args:expr):%) => { $crate::__private_api::capture_display(&&$args) }; (($args:expr):display) => { $crate::__private_api::capture_display(&&$args) }; //Error (($args:expr):err) => { $crate::__log_value_error!($args) }; // sval::Value (($args:expr):sval) => { $crate::__log_value_sval!($args) }; // serde::Serialize (($args:expr):serde) => { $crate::__log_value_serde!($args) }; } #[doc(hidden)] #[macro_export] #[cfg(not(feature = "kv"))] macro_rules! __log_value { ($($args:tt)*) => { compile_error!("key value support requires the `kv` feature of `log`") }; } #[doc(hidden)] #[macro_export] #[cfg(feature = "kv_sval")] macro_rules! __log_value_sval { ($args:expr) => { $crate::__private_api::capture_sval(&&$args) }; } #[doc(hidden)] #[macro_export] #[cfg(not(feature = "kv_sval"))] macro_rules! __log_value_sval { ($args:expr) => { compile_error!("capturing values as `sval::Value` requites the `kv_sval` feature of `log`") }; } #[doc(hidden)] #[macro_export] #[cfg(feature = "kv_serde")] macro_rules! __log_value_serde { ($args:expr) => { $crate::__private_api::capture_serde(&&$args) }; } #[doc(hidden)] #[macro_export] #[cfg(not(feature = "kv_serde"))] macro_rules! __log_value_serde { ($args:expr) => { compile_error!( "capturing values as `serde::Serialize` requites the `kv_serde` feature of `log`" ) }; } #[doc(hidden)] #[macro_export] #[cfg(feature = "kv_std")] macro_rules! __log_value_error { ($args:expr) => { $crate::__private_api::capture_error(&$args) }; } #[doc(hidden)] #[macro_export] #[cfg(not(feature = "kv_std"))] macro_rules! __log_value_error { ($args:expr) => { compile_error!( "capturing values as `std::error::Error` requites the `kv_std` feature of `log`" ) }; }