Yes, thanks for your comment.

• The expected result doesn't correspond to the description
  Ok.
  More simple, and more clear.
• "Return a value" is not a kata, that's a joke
  Ok.
  I enjoyed practicing hundreds 8 Kyu Kata

Thanks. Sorry for my french

Thanks for your comment.
The Kata should propose "a short" solution and "a complete" solution ?

for Ruby : very instructive if you can explain 8 Kyu the difference between ===> "class method", accessed directly from the class AND ===> "instance method", accessed from an object instance from a class. Thanks