emmott-15MBPi7:~ fredemmott$ irb
irb(main):001:0> require 'active_support/core_ext/array/random_access'
=> true
irb(main):002:0> def flip *x
irb(main):003:1> x.sample
irb(main):004:1> end
=> nil
irb(main):005:0> flip :foo, :bar
=> :bar
irb(main):006:0>