==== Summary

Swap allows dynamically replacing and restoring methods.
Useful as a stubbing device, as it allows unstubbing as well.

==== Examples

  require 'swap'

  class User
    extend Swappable

    attr_writer :name
    def name
      @name
    end
  end

  user = User.new
  user.name = 'martin'
  user.name #=> 'martin'

  User.swap!(:name) { @name.reverse }
  user.name #=> 'nitram'

  User.unswap!(:name)
  user.name #=> 'martin'

Calling #unswap! without argument will restore all swapped methods.

See also examples/simple.rb