https://github.com/rubyworks/clik

Kernel#cli
https://github.com/rubyworks/clik

Last synced: 6 months ago
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Kernel#cli

• Host: GitHub
• URL: https://github.com/rubyworks/clik
• Owner: rubyworks
• License: other
• Created: 2013-03-07T14:51:35.000Z (almost 13 years ago)
• Default Branch: master
• Last Pushed: 2014-12-27T17:02:55.000Z (about 11 years ago)
• Last Synced: 2024-11-15T18:09:13.716Z (over 1 year ago)
• Language: Ruby
• Size: 206 KB
• Stars: 97
• Watchers: 7
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: HISTORY.md
  • License: LICENSE.txt

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README

          
# CLI.K

[Website](http://github.com/rubyworks/clik) /

[Documentation](http://rubydoc.info/gems/clik/frames) /

[Report Issue](http://github.com/rubyworks/clik/issues) /

[Source Code](http://github.com/rubyworks/clik)    

[![Flattr Me](http://api.flattr.com/button/flattr-badge-large.png)](http://flattr.com/thing/324911/Rubyworks-Ruby-Development-Fund)

## About

CLI.K stands for Command Line Interface in the Kernel. It provides a very 

simple `cli` method for parsing command line options.

## Status

[![Gem Version](https://badge.fury.io/rb/clik.png)](http://badge.fury.io/rb/clik)

[![Build Status](https://travis-ci.org/rubyworks/clik.png)](https://travis-ci.org/rubyworks/clik)

## Usage

### They call it "K.I.S.S."

Usage is very straightforward, although it might look a little odd at first

glance:

```ruby

  require 'clik'

  cli '-f --file'  => lambda{ |f| @file = f },

      '-d --debug' => lambda{ $DEBUG = true },

      '-h --help'  => lambda{ show_help }

```

There's very little to it really. The `cli` command simply maps command

line options to procedures which are used to process them. That's it.

In our example, notice that `-f` and `--file` are easily defined as 

synonymous options. Simple. Then notice that the `-f/--file` option's

procedure takes an argument, so the command line option takes an argument 

as well. Again simple.

The cli method has a few additional niceties. It can handle run-on flags,

i.e. `-abc` is the same as `-a -b -c`. And you can pass it an alternate

set of arguments to parse, as the first argument, to use something other 

than the default `ARGV`.

```ruby

  argv = ['--testing']

  cli argv,

    ...

```

### You need help, no you really don't

At this point, you might be wondering about help output. Clearly there are

no descriptions given in our example. Well, guess what! It's really easy

to print something out yourself. In fact, if you really want to *do it right*,

create a manpage with [ronn](git://github.com/rtomayko/ronn.git) or

[md2man](https://github.com/sunaku/md2man), and impress your friends.

It's a much better approach then jamming all that verbiage into the command

line options parser code.

### Ask and you shell receive

In addition to #cli, CLI.K provides the #ask method. This is a very simple

command line query method.

    ans = ask "Are you nice? [Y/n]"

Other Ruby libraries have their own take on the #ask method, and this very

simple implementation can just as soon be overridden. No biggy. But it's nice

to have for simple use cases.

## Acknowledgments

We have to give credit where credit is due. This interface is the great 

achievement of Michel Martens, who created the original [Clap](https://github.com/soveran/clap)

library from which CLI.K evolved. Mr. Martens deserves high praise for this

design. It's not easy to realize that this level of simplicity is all one

really needs! Thank you, Michel!

## Copyrights & License

CLI.K is copyrighted open-source software.

    Copyright (c) 2013 Rubyworks

CLI.K is base on Michel Marten's Clap library.

    Copyright (c) 2010 Michel Martens

See LICENSE.txt and NOTICE.txt files for details.