Recursion play

recursion_play.rb

def append(ary, n)
  return ary if n < 0
  return append((ary.push n), n-1)
end

appended = append [], 2
puts appended.inspect # => [2, 1, 0]

def prepend(ary, n)
  return ary if n < 0
  return prepend((ary.unshift n), n-1)
end

prepended = prepend [], 2
puts prepended.inspect # => [0, 1, 2]