luhnacy

A tiny (hopefully) gem that will automate some of the painful tasks of generating / validating strings of numbers based on the Luhn algorithm (e.g. credit card numbers, ID numbers).

Usage

To require:

require 'luhnacy'

To validate:

Luhnacy.valid?('49927398716')

To generate a string of 10 digits that satisfies the Luhn algorithm:

valid_string = Luhnacy.generate(10)

To generate a string of 10 digits that does not satisfy Luhn algorithm:

invalid_string = Luhnacy.generate(10, :invalid => true)

Note on Patches/Pull Requests

• Fork the project.

• Make your feature addition or bug fix.

• Add tests for it. This is important so I don’t break it in a future version unintentionally.

• Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)

• Send me a pull request. Bonus points for topic branches.

Sources

• blog.flame.org/2008/3/24/checking-credit-card-numbers-in-ruby

• www.missiondata.com/blog/web-development/25/credit-card-type-and-luhn-check-in-ruby/

• en.wikipedia.org/wiki/Luhn

Copyright

Copyright © 2010 Rory McKinley. See LICENSE for details.