2017-04-26

Do NOT enumerate Enumerators

During a take on a Euler Problem, I stumbled upon a quirky behaviour:

(3..100).step(2)
=> #<Enumerator: ...>

so you can do something like this, neglecting .each:

(3..100).step(2) { |e| e.nil? }

which is a tiny bit faster than using each for iterating.