Ruby Hash with duplicate keys?
Two ways of achieving duplicate keys in a hash: h1 = {} h1.compare_by_identity h1[“a”] = 1 h1[“a”] = 2 p h1 # => {“a”=>1, “a”=>2} h2 = {} a1 = [1,2,3] a2 = [1,2] h2[a1] = 1 h2[a2] = 2 a2 << 3 p h2 # => {[1, 2, 3]=>1, [1, 2, 3]=>2}