Today's Kata 11-03-2015

plus_minus.rb

# For today, here's the problem for today
# Do whatever you need to do to Ruby, such that I can say: 9 - 8, and the answer will be 17
# And if I say 9 + 8, the answer will be 1
# so - i load whatever code you want to give me via a console, and I should be able to do the above
# turn plus into minus, minus into plus
# a short sentence explaining what you did and why it works would be nice

class Fixnum
  alias_method :temp, :+
  alias_method :+, :-
  alias_method :-, :temp
end

gem 'minitest', '>= 5.0.0'
require 'minitest/autorun'

class TestMinusPlus < Minitest::Test
  def test_minus
    assert_equal 17, 9 - 8
  end

  def test_plus
    assert_equal 1, 9 + 8
  end
end