Comment by cactus2093 | Hacker News Reader

Comment by cactus2093 | Hacker News Reader

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> Most of the designed in extensibility I've seen predicted the wrong sort of extension that would be needed anyway.

I definitely agree with that, and I think a preference for more verbose code is actually very compatible with this idea. Verbosity is not the same as over-complicating or over-abstracting things. In my experience a lot of the time it's actually the drive to avoid verbose code that causes these problems in the first place.

For instance, you have two functions that are similar but with some important difference, and the developer decides that anything that resembles duplication is bad and refactors them into a single abstraction. This type of thing can cause much more harm than just leaving in a little bit of verbosity by keeping the functions independent of each other.

One way to analyze the two similar function situation is to ask whether a future change in the logic to one would imply that a change should also made to the other.

If so, then by keeping them separate, you introduce the risk that you would forget to update the other. Using a single function and calling it twice, even with different parameters, is a way communicating that it's important that the semantics be tied.

If a change in one wouldn't imply a change in the other, then you really have two separate semantic roles being played that happened to resemble each other in implementation - harmless incidental duplication.

What if a change to one would imply a change to the other, but also the block of code is needed in 20 places instead of two?

> to ask whether a future change in the logic to one would imply that a change should also made to the other.

If there's a really obvious answer to that question, then great. But often the answer is "sometimes" or even "most of the time". We train most developers beginning even in intro-level programming classes to err on the side of deduplication and over-abstracting in these cases, but the longer I've been working as a developer the more I have come to think it's better to err on the side of allowing some duplication except in the most clear cut of cases.

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