to_proc Symbol to_proc Symbol Symbol#to_proc idiom (1..100).map(&:to_s) (1..100).map{|x| x.to_s } Proc#curry .
x x - 1) plus_five = proc { |x,y,z| x + y + z }.curry.call(2).call(3) plus_five[10] #=> 15 plus_five [] Proc#curry