Question

Trying to get the values out of a collection that could be either an Array or a Hash, but switching based on type seems awkward:

def values_from_collection(array_or_hash)
  case array_or_hash
  when array_or_hash.is_a? Array
      array_or_hash
  when array_or_hash.is_a? Hash
      array_or_hash.values
  end
end 

Is seems like there should be a single interface/method that both classes support, but nothing obvious stands out in Enumerable. Is there a standard way to accomplish this?

Answer 1

Well, it doesn’t seem so to me. Hash and Array are very different data structures. Why do you think they should support this?

Anyway, you could, for example, monkey-patch Array class to add values method

class Array
  def values
    self
  end
end

And then your method is greatly simplified:

def values_from_collection(array_or_hash)
  array_or_hash.values
end 

But this is worse than branching, in my opinion.