//! An example using the Builder pattern API to configure the logger at run-time based on command //! line arguments. //! //! The default output is `module::path: message`, and the "tag", which is the text to the left of //! the colon, is colorized. This example allows the user to dynamically change the output based //! on command line arguments. //! //! The [clap](https://crates.io/crates/clap) argument parser is used in this example, but loggerv //! works with any argument parser. extern crate ansi_term; #[macro_use] extern crate log; extern crate loggerv; extern crate clap; use clap::{Arg, App}; fn main() { // Add the following line near the beginning of the main function for an application to enable // colorized output on Windows 10. // // Based on documentation for the ansi_term crate, Windows 10 supports ANSI escape characters, // but it must be enabled first using the `ansi_term::enable_ansi_support()` function. It is // conditionally compiled and only exists for Windows builds. To avoid build errors on // non-windows platforms, a cfg guard should be put in place. #[cfg(windows)] ansi_term::enable_ansi_support().unwrap(); let args = App::new("app") .arg(Arg::with_name("v") .short("v") .multiple(true) .help("Sets the level of verbosity")) .get_matches(); loggerv::init_with_verbosity(args.occurrences_of("v")).unwrap(); error!("This is always printed to stderr"); warn!("This too is always printed to stderr"); info!("This is optional info printed to stdout"); // for ./app -v or higher debug!("This is optional debug printed to stdout"); // for ./app -vv or higher trace!("This is optional trace printed to stdout"); // for ./app -vvv }