I've been using this pattern a lot in ruby, and I was wondering if there's a better way to do this. It kinda feels like its perverting the use of the reduce function when all I really want to do is split a list into a list of lists by a specific field value.

gistfile1.rb

def split_list_by list, &block
  list.reduce({}) {|memo, v|
    key = yield v
    
    memo[key] ||= []
    memo[key] << v
    
    memo
  }.map{|k, v|
    v
  }
end