Implementation of Clojure get-in for Ruby hashes

hash_extensions.rb

class Hash
  def get_in(*keys)
    key = keys.first
    value = self[key]
    return value if keys.count == 1 
    return nil if keys.count > 1 and !value.respond_to? :get_in
    return value.get_in(*keys.drop(1)) if key?(key)
  end
end

h = {:a => {:b => {:c => 1}}, b: 2, x: {y: "yikes"}}
puts h.get_in(:a, :b, :c)
puts h.get_in(:b, :g, :f)
puts h.get_in(:x, :y, :z)
puts h.get_in(:x, :y)
puts h.get_in(:x)