getopt library For Go

This is a very simple library for getopt-style argument/option parsing, written in and for Go. It supports both traditional "short" options (like -a, -b 1, -dfe, etc), and the GNU-style "long" options (like --help, --fix=everything, etc).

I strongly believe that exposing a common and familiar user interface in your programs is important; the getopt-style command line argument parsing is the single most universally accepted convention, dating back to at least 1980, and widely supported by many platforms, languages, and utilities.

Unfortunately, Go's standard flag module ignores that convention, and proposes its own. This package offers a simple alternative.

Example

You can find more examples in the examples directory of the source distribution.

package main

import (
	"github.com/rollcat/getopt"
	"os"
)

func main() {
	args, opts, err := getopt.GetOpt(
		os.Args[1:],
		"hv",
		nil,
	)
	if err != nil || len(args) > 0 {
		println("Usage: program [-hv]")
		os.Exit(1)
	}
	for _, opt := range opts {
		switch opt.Opt() {
		case "-v":
			println("Version 0.1")
			os.Exit(0)
		case "-h":
			println("Usage: program [-hv]")
			os.Exit(0)
		default:
			panic("unexpected argument")
		}
	}
}

Documentation

On pkg.go.dev.

You can also use godocs, or the command line:

go doc github.com/rollcat/getopt

Author and license

Original code by Tim Henderson <tim.tadh@gmail.com>.

This fork, and all of its opinionated tweaks, by Kamil Cholewiński <kamil@rollc.at>.

License is BSD.