Group Hash by values in ruby

Question

I have a hash in ruby which looks something like this:

{
  \"admin_milestones\"=>\"1\",
  \"users_milestones\"=>\"0\",
  \"admin_goals\"=>\"1\",
  \         


        

Answer 1

Similar with https://stackoverflow.com/a/56164608/14718545 you can use group_by but with then, in this case, you will avoid instantiating an extra variable.

{
  "admin_milestones" => "1",
  "users_milestones" => "0",
  "admin_goals" => "1",
  "users_goals" => "0",
  "admin_tasks" => "1",
  "users_tasks" => "0",
  "admin_messages" => "1",
  "users_messages" => "0",
  "admin_meetings" => "1",
  "users_meetings" => "0"
}.then { |h| h.keys.group_by { |k| h[k] } }

{"1"=>["admin_milestones", "admin_goals", "admin_tasks", "admin_messages", "admin_meetings"],
 "0"=>["users_milestones", "users_goals", "users_tasks", "users_messages", "users_meetings"]}