instiki/vendor/rails/activesupport/lib/active_support/core_ext/integer/even_odd.rb

module ActiveSupport #:nodoc:
  module CoreExtensions #:nodoc:
    module Integer #:nodoc:
      # For checking if a fixnum is even or odd.
      #
      #   2.even?  # => true
      #   2.odd?   # => false
      #   1.even?  # => false
      #   1.odd?   # => true
      #   0.even?  # => true
      #   0.odd?   # => false
      #   -1.even? # => false
      #   -1.odd?  # => true
      module EvenOdd
        def multiple_of?(number)
          self % number == 0
        end

        def even?
          multiple_of? 2
        end if RUBY_VERSION < '1.9'

        def odd?
          !even?
        end if RUBY_VERSION < '1.9'
      end
    end
  end
end