Monday, February 09, 2015

Gimme Structure

"I believe that it may happen that one will succeed, and one must not begin to despair, even though defeated here and there; and even though one sometimes feels a kind of decay, though things go differently from the expected, it is necessary to take heart again and new courage. For the great things are not done by impulse, but by a series of small things brought together. And great things are not something accidental, but must certainly be willed. What is drawing? How does one learn it? It is working through an invisible iron wall that seems to stand between what one feels and what one can do.”
-- Vincent Van Gogh

I used to think what I was looking for was good design. On more cynical days I'd settle for any design, or not even design, just some kind of structure.

I guess that's a bit like saying you want "quality". Would that be good quality or bad quality? Obviously, good structure is better than bad structure. But even bad structure is better than no structure.

I see, and work with, a lot of bad code, some of it written by my programmers, some of it (sadly) written by myself. The code seems to be split up into methods and classes more or less randomly. Names of variables and methods make no sense or are even outright misleading. It might work (most of the time) but it is difficult to understand, usually has duplication, commonly has logic errors, often old dead code, incorrect comments, etc. It will come as no surprise that it is hard to modify.

Part of the problem is incremental development. Even if there was some structure at some point, unless everyone modifying the code pays attention to maintaining that structure, it will degrade. And if it didn't have much structure to begin with it's even worse.

I don't think you can blame this on "evolution". Bad code is not very "fit". Natural selection would soon kill it off. Evolution is not intelligent design, but it comes up with lean, efficient solutions. It's not sloppy.

Much of the blame goes back to a common weakness in programmers - thinking that you are done when you have something that appears to work. Not going the extra distance to make sure it's readable, understandable, logically complete and correct. Often not even bothering to take care of the low hanging fruit like variable and method names.

And of course, once the code is a tangled mess no one wants to touch it to clean it up. Understandably, since it's a lot of work. And there's no doubt unobvious behavior in that code that you need to figure out and preserve. And there's a high risk of breaking things, and many programmers pay more attention to fear than to any desire for good code.

I have no silver bullets. Just a plea - please try to write code with some sort of comprehensible structure, for your own sake if nothing else.

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