{|x| x _ x} Developer T-Shirt

Slash Star Verified independent store

→

{|x| x * x} is a Ruby block: the |x| names the parameter, and the body squares it. Hand it to a method like map and it runs once per element — [1,2,3].map { |x| x * x } gives [1,4, 9]. The anonymous function Ruby threads through nearly everything it does, written inline at the point you need it. Show more