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Intermediate variables, organizing OO, meeting Grinders half way

I work with Dave Copeland at LivingSocial, but not on the same team. Maybe someday I’ll fix that, but for now I learn a lot from his writings. Herein, a few things worth checking out yourself.

If you ever need to read my code, you’ll eventually come to suspect I have a particular dislike for intermediate variables. You’ll come to suspect this through finding lots of uses of inject and tap, two Ruby methods not everyone is on good terms with. You can imagine I’d side with Dave on the subject of Tap versus intermediate variables. You’d be right, but Dave says it so well, you should read his take on the joy of tap. He also shows how to annoy people with tap-like constructs in other languages. If you’re into combinators, Reg Braithwaite has written about tap in terms of Kestrels.

I’ve been learning a lot about how to think about organizing a non-trivial object-oriented system this year. Gary Bernhardt is doing some fantastic work explaining a hybrid imperative/object/functional system. If you don’t have time to dive into Gary’s entire backlog (it’s worth it to find the time), Dave covers some similar ground describing the only four types of classes in your OO system. Think of these as a post-hoc observation on how many systems seem to evolve; Record objects take root, Service objects reveal themselves (often intertwined amongst other objects), Builders are sprinkled throughout, and there are a few classes hanging out that you wish you’d made immutable. These are handy guides for thinking about and refactoring an existing design. That said, I think it would be overkill to start a design with these archetypes. Caveat: some developers will really dislike organizing a system this way; tread carefully.

I’ve written about the virtues of The Grinder. I know a lot of non-Grinders wish that the Grinder knew more about how to take the code they’ve made to work and improve it so that it is more malleable in the future. Making it Right: Technical Debt vs. Slop sets out a good mindset on how this can happen. Think before you type, write a test, make it work, and then tidy it up with future malleability in mind. From there, non-Grinders need to meet Grinders in the middle is in shrinking the feedback cycle. When tests are too much effort to write or take too long to run, Grinders fall back to their old habits. When making it right involves too many intermediate steps with nothing to show for it, Grinders move on to the next thing. When a non-Grinder learn to be less precious with our work, or a Grinder learns to take a moment to round off the sharp corners on their work, you end up with a much stronger team. Fight for it.

By Adam Keys

Telling a joke. Typing.