In Ruby on Rails 3.2.2, I encountered an error when I wrote validation processing in a model and tried to run it.

■ Error Message

Range unspecified. Specify the :in, :within, :maximum, :minimum, or :is option.

■ Source Code (partial)

class Article < ActiveRecord::Base
  validates :title,
    length: { minimun: 0, maximun: 50 }
end

The cause was spelling mistakes in minimum and maximum.

◯ minimum ☓ minimun

◯ maximum ☓ maximun

That’s all from the Gemba.