|XP is just a number|
Re: Re: Re: Short routines matter more in OO?by demerphq (Chancellor)
|on Oct 13, 2003 at 21:04 UTC||Need Help??|
Im very glad you spoke up in this column. I don't agree that short subroutines are necessarily more understandable and easier to manage. In fact on the contrary. I've found that short subroutines and methods make understanding the code flow of a program much more difficult. (As yourself and others such as Corion have pointed out.) Your comments here have articulated what I've thought (or felt) when I've seen this argument before. I hate dealing with code where methods only do one or two lines of action and there are many many such methods and subs. By the time I trace through a horrible maze of tiny subs each almost identical to the next my head hurts, I can't get a mental model of the program flow (and I typically want to fly to Australia to strangle the author responsible :-)
As you said elsewhere, subroutines and methods should be a small and as simple as they can be and get the job done. They shouldn't do multiple things and be huge monstrosities but at the same time they shouldn't be sliced up into bits that are only going to be called from one place.
For me a sub/method should do a single conceptual task. If that means it ends up quite long (over 50 lines or so) then so be it. I certainly don't spend a lot of time worrying how long my subs are.
Once again thanks. Tis a pitty you are anonymous or I would follow the nodes you write on a regular basis.
One last thought though. I think this particular subject has different levels. Experienced programmers can probably argue against tillys advice. We have the knowledge to decide when to sacrfifice a rule of thumb like "keep your subroutine short" on the altar of pragmatism. But for a beginner I think the advice "keep your subroutines short and your methods shorter" is probably sound. Until they have developed a more sophisticated basis by which to decide the rule is probably a sound design/craft guideline. The more you know a subject the easier it is to decide "when to break the rules".
So thanks to tilly for yet another thought provoking thread, and thanks to yourself for a bit of evidence of the contrary view.
First they ignore you, then they laugh at you, then they fight you, then you win.