//! logger library

   with_thread, AdaptiveFormat, Duplicate, FileSpec, Logger, LoggerHandle,

 };

 mod err;

 /// initialize a simple logger

 pub fn simple() -> Result<()> {

   log::set_logger(&SimpleLogger)

     .map(|()| log::set_max_level(LevelFilter::Trace))?;

   Ok(())

 }

 /// a simple logger

 struct SimpleLogger;

 impl log::Log for SimpleLogger {

   fn enabled(&self, metadata: &Metadata) -> bool {

     metadata.level() <= Level::Info

   }

   fn log(&self, record: &Record) {

     if self.enabled(record.metadata()) {

       println!("{} - {}", record.level(), record.args());

     }

   }

   fn flush(&self) {}

 }

 /// Initialize a `Logger` with a specified logging level

 pub fn flexi(level: &str) -> Result<()> {

   Logger::try_with_env_or_str(level)?

     .format(flexi_logger::colored_default_format)

     .set_palette("196;208;50;7;8".to_string())

     .adaptive_format_for_stderr(AdaptiveFormat::Detailed)

     .adaptive_format_for_stdout(AdaptiveFormat::Default)

     .log_to_stdout()

     .start()?;

   Ok(())

 }

 /// Initialize file Logger

 pub fn file(env: &str, log_path: &str, log_name: &str) -> Result<LoggerHandle> {

   Ok(

     Logger::try_with_env_or_str(env)?

       .log_to_file(

         FileSpec::default()

           .suppress_timestamp()

           .directory(log_path)

           .basename(log_name)

           .suffix("log"),

       )

       .format_for_files(with_thread)

       .append()

       .duplicate_to_stdout(Duplicate::Error)

       .start()?,

   )

 }