cmdr helps writing command-line programs with subcommands in Go.

example.go:

package main
import (
  "github.com/rsms/cmdr"
)

var quiet = false
var rootDir = "."

var version = cmdr.Cmd("version", "Show version", func () {
  println("cmdr example v1.2.3")
})

var foo = cmdr.Cmd("foo", "Example command", func (opt *struct {
  FooBar      bool     `        Bar the foo with some bar`
  FirstName   string   `="John" Name of a cool person`
  Dir         string   `?"."    Directory to list`
  File        []string `!       Some files`
}, cmd *cmdr.Command) {
  if !quiet {
    cmd.Logf("foo command run with opt=%+v", opt)
  }
  // Do something useful
})

func main() {
  cmdr.BoolVar(&quiet, "quiet", false, "Suppress status messages")
  cmdr.StringVar(&rootDir, "root-dir", rootDir, "Directory to start in")
  cmdr.Main()
}

Output:

$ go build
$ ./example -h
Usage: ./example [options] <command>
Options:
  -quiet false    Suppress status messages
  -root-dir "."   Directory to start in
Commands:
  foo [<dir>] <file>...  Example command
  version                Show version
  help <cmd>             More information about a command

$ ./example version
cmdr example v1.2.3
$ ./example help foo
Example command
Usage: ./example foo [options] [<dir>] <file>...
Options:
  -first-name "John"   Name of a cool person
  -foo-bar             Bar the foo with some bar
Arguments:
  <dir>       Directory to list (default: ".")
  <file>...   Some files 
$ ./example foo --first-name "Lisa" -foo-bar=false hello *.go
foo command run with opt=&{FooBar:false FirstName:Lisa Dir:hello File:[example.go]}
$

Copyright (c) 2015 Rasmus Andersson http://rsms.me/

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

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