logger

type Log interface {

	// Writer returns a new io.Writer that writes to the log output for the given log level.
	Writer(level LogLevel) io.Writer

	// PWriter returns a new io.Writer that writes to the log output for the given log level with a prefix.
	PWriter(label string, level LogLevel) io.Writer

	// NameSpace returns a new Log with the given label as the prefix.
	NameSpace(label string) Log

	// SetOutput sets the output for the given log level.
	SetOutput(level LogLevel, w io.Writer)

	// SetLevel sets the current log level.
	//
	// Log messages with a log level lower than the current log level will not be written.
	SetLevel(level LogLevel)

	// Log a debug message.
	Debug(args ...interface{})

	// Log an info message.
	Info(args ...interface{})

	// Log a warning message.
	Warn(args ...interface{})

	// Log an error message.
	Error(args ...interface{})

	// Log a message and exit the program with the given error code.
	Fatal(errorcode int, args ...interface{})

	// Log a format- and args-based debug message.
	Debugf(format string, args ...interface{})

	// Log a format- and args-based info message.
	Infof(format string, args ...interface{})

	// Log a format- and args-based warning message.
	Warnf(format string, args ...interface{})

	// Log a format- and args-based error message.
	Errorf(format string, args ...interface{})

	// Log a format- and args-based message and exit the program with the given error code.
	Fatalf(errorcode int, format string, args ...interface{})

	// Log a message at the given log level.
	Log(level LogLevel, args ...interface{})

	// Log a format string at the given log level.
	Logf(level LogLevel, format string, args ...interface{})

	// WriteString writes a string to the log output.
	WriteString(s string) (n int, err error)
}

type LogLevel int8

type LogWriter struct {
	Logger *Logger
	Level  LogLevel
}

type Logger struct {
	// Level is the log level.
	Level LogLevel

	// Prefix is the prefix for each log message.
	Prefix string

	// Suffix is the suffix for each log message.
	Suffix string

	// Display a timestamp alongside the log message.
	OutputTime bool

	// Outputs for the log messages.
	OutputDebug io.Writer
	OutputInfo  io.Writer
	OutputWarn  io.Writer
	OutputError io.Writer

	// WrapPrefix determines how the prefix should be wrapped
	// based on the LogLevel.
	WrapPrefix func(LogLevel, string) string
}