// log.Default() includes timestamps
log.Info("Hello world!")
// Output: 2023/01/23 14:23:45 INFO Hello world!

// log.New() does not
logger := log.New(os.Stderr)
logger.Info("Hello world!")
// Output: INFO Hello world!

func New(w io.Writer) *Logger {
    return NewWithOptions(w, Options{
        ReportTimestamp: true,
    })
}

logger := log.NewWithOptions(os.Stderr, log.Options{
    ReportTimestamp: false,
})

handler := log.NewWithOptions(os.Stderr, log.Options{
    ReportTimestamp: true,
    Level:           log.DebugLevel,
})
logger := slog.New(handler)

// HandlerOptions provides slog-style configuration.
type HandlerOptions struct {
    AddSource bool
    Level     Level
}

// NewTextHandler returns a Handler with text formatting.
// Timestamps are enabled by default.
func NewTextHandler(w io.Writer, opts *HandlerOptions) *Logger {
    if opts == nil {
        opts = &HandlerOptions{}
    }
    return NewWithOptions(w, Options{
        ReportTimestamp: true,
        Formatter:       TextFormatter,
        Level:           opts.Level,
        ReportCaller:    opts.AddSource,
    })
}

// NewJSONHandler returns a Handler with JSON formatting.
// Timestamps are enabled by default.
func NewJSONHandler(w io.Writer, opts *HandlerOptions) *Logger {
    if opts == nil {
        opts = &HandlerOptions{}
    }
    return NewWithOptions(w, Options{
        ReportTimestamp: true,
        Formatter:       JSONFormatter,
        Level:           opts.Level,
        ReportCaller:    opts.AddSource,
    })
}

handler := log.NewTextHandler(os.Stderr, &log.HandlerOptions{
    Level: log.DebugLevel,
})
logger := slog.New(handler)