= Luhn Gem

Luhn checksum algorithm gem, credit card generation and validation


== Usage

While credit card validation routines abound, it's still nice have a window open and 
crank out test cards during web development:

  $ irb -rubygems -r luhn
  irb(main):001:0> Luhn.generate  
  => "4354135477199499" # defaults to :visa, but also can be in [:mast,:disc,:amex]
  irb(main):002:0> Luhn.generate(:visa)
  => "4076900550063889"

Of course if you just want the Luhn checksum, you can do:

  Luhn.checksum("1234321") # => 4

To validate the checksum of a decimal string (as opposed to the full-context validity)

  Luhn.checksum_valid?("1234321")          # => false
  Luhn.checksum_valid?("4076900550063889") # => true
  Luhn.checksum_valid?("4076900550063888") # => false


= Downloading

Note: not yet registered as a rubyforge gem

git://github.com/pliam/luhn_gem.git


= Copying

Copyright (c) 2008 John Pliam, released under the MIT license