Ruby's Struct is pretty nifty. Person = Struct.new :name, :age people = [ Person.new('Alice', 42), Person.new('Bob', 23), Person.n

Ruby's Struct is pretty nifty. Person = Struct.new :name, :age people = [ Person.new('Alice', 42), Person.new('Bob', 23), Person.new('Carol', 30) ] people.sort_by(&:age).map(&:name) # => ["Bob", "Carol", "Alice"]