Ruby array of hash. group_by and modify in one line

Question

I have an array of hashes, something like

[ {:type=>\"Meat\", :name=>\"one\"}, 
  {:type=>\"Meat\", :name=>\"two\"}, 
  {:type=>\"Fruit\", :n         


        

Answer 1

In a single iteration over initial array:

arry.inject(Hash.new([])) { |h, a| h[a[:type]] += [a[:name]]; h }