As a separate point, I almost never implement each on a custom object in ruby. There are probably "library code" cases where it's appropriate Likewis

As a separate point, I almost never implement each on a custom object in ruby. There are probably "library code" cases where it's appropriate Likewise. I've worked with Ruby fulltime since 2014 and never done it in actual project code, only in book exercises, and I'm not sure I've seen it in any gems I've dove into, though I've never poked around in ActiveRecord. Like you said, I can't think of too many reasons why one would want to implement #each -- on a daily basis I'm just putting various objects into arrays, hashes, etc. I tend to write very "boring" Ruby. Ruby gives you lots of ways to get wacky, but IMO the default best practice would be to keep it simple and avoid the cute stuff unless you really have a reason.