Performance differences seem negligible gist.github.com/jodosha/229951

As for better/cleaner, Rubyists definitely love .each, and for practical purposes, it's probably worth just drinking the kook-aid rather than stirring things up with Ruby dogma.

But I'm happy to hear the bikeshedding on this. 😄

One thing to think about is that the for counter in 1..5 is really only used for looping syntax, whereas most other ruby Enumerable methods like #map and #reduce have similar syntax as #each, so consistency is likely a factor in why people prefer one over the other.

Given this:

banana = { name: "banana", flavor: "sweet", texture: "soft" }
apple = { flavor: "sweet", texture: "crispy" }
grapefruit = { name: "grapefruit", flavor: "sour", texture: "juicy" }

fruit_basket = [banana, apple, grapefruit]

for fruit in fruit_basket
  puts "#{fruit[:name]} is #{fruit[:flavor]}"
end

fruit_basket.each do |fruit|
  puts "#{fruit[:name]} is #{fruit[:flavor]}"
end

I would say, yeah there's not much of a difference in terms of readability.

BUT there is a good reason. Try running this code example:

Basically, for..in loop can redefine things that you didn't intend to, and that can cause problems.

Reference: Tutorials Point - Ruby Loops

Firstly, thank you for the explanation.

Secondly, I really like the for .. in syntax, although in Ruby (don't know if it's the same for JavaScript), counter cleanup is non existent.

Thirdly (is that a word?): What is rubocop?