Naming is abstraction

24 Oct 2016. comments

The point of choosing good names in software development is that it provides abstraction for others. Good names don’t exist for compilers because the compiler isn’t going to care about names at all. Naming is not just some process invented by language designers to make you box up your code arbitrarily. A good name exists so that when you look at code that I wrote (or I later look at code I wrote) I can understand at a glance what responsibilities it has and what it might be doing. I covered this in a previous post: Readable is not Elementary.

Let’s say someone on your team submits a code review to you and you open it up and find this method call:

manager.process(foo)

This isn’t a good name. What does process mean in this case? What are we doing with foo? What does manager manage? What does ‘managing’ even mean in this case?

The problem with the above code is that it failed to abstract the inner concepts from humans. The practical implication of this poorly named method is that you and every other programmer who comes across it will have to dive inside of it to understand what it’s doing. That’s a failed abstraction because nothing got abstracted for you if you had to open it up. The method name wasn’t clear so you don’t know what you’re getting into when you call it. It’s as if there was no point to putting its contents inside the method and could have just inlined its contents.

What if the above code instead looked like this:

investors.distribute_funds_equally(money)

Do you need to dive into the method to understand it now? No, not really, because the abstraction is clear. You don’t need to know the specifics of the internals of this method because the person who wrote it wanted to communicate to you what was going on inside of it by expressing a clear name. Time is saved because you now have less surface area of the code to think about and the implementation of that method is free to be refactored so long as it upholds the responsibilities that it advertises.

comments

Tagged: software craftsmanship encapsulation abstraction naming

2017 Ben Lakey

The words here do not reflect those of my employer.