Comments on: The Zen of Doing It Wrong

By: Mike Pirnat » The Diaper Pattern Stinks

Mike Pirnat » The Diaper Pattern Stinks — Sat, 09 May 2009 19:49:10 +0000

[...] mentioned the “Diaper Pattern” in a recent post and got some comments asking what the term meant. I had hoped to just link to an explanation, [...]

By: Marius Gedminas

Marius Gedminas — Thu, 07 May 2009 11:44:27 +0000

So, what’s a Diaper Pattern?

By: robert

robert — Thu, 07 May 2009 06:16:03 +0000

at least a single try-except block like this could probably be easily found in my code. and actually, other than being more code than necessary, i don’t think there’s a big problem with this. typically, i comment out the raise to do some testing. but i agreee, if production code means, all testing has been done – or is automated – superfluous code should be removed.

By: guilty

guilty — Thu, 07 May 2009 02:42:45 +0000

hi,

I think I can explain the reason for this ugly code… I think

I bet the code at some point had some debugging code in there. So there was a problem with the file operations perhaps.

These try: raise: pairs allow you to quickly add some debugging code in there.

Then when the code was finished, the programmer left it in there in case they needed to do some more debugging later. So it was never cleaned up.

The pass were left in case the raise was to be removed… as I expect for the same reason it was left in.

Just some guesses… maybe I’ve done similar ugly things in the past, and that’s why I might have done this.

I guess in this case, it’s similar to using these other ugly things…

# easily disable a block by changing one character.
if 0:
do_stuff()

if 1:
do_stuff()

// allow putting more than one thing in the if/else blocks…
// if you need to later.
// Since C doesn’t require {} for single statements.
if(some_condition) {
do_one_thing()
} else {
do_one_thing()
}

Leaving ugly stuff like that in production code, lets you try and fix things quicker if needed.

cu,

By: mpirnat

mpirnat — Wed, 06 May 2009 20:43:26 +0000

@Christian Wyglendowski Instead of the "none shall pass" Black Knight, I'm more envisioning Gandalf the Grey catching exceptions at the Bridge of Khazad-Dum, declaring "You *cannot* pass!"

By: Christian Wyglendowski

Christian Wyglendowski — Wed, 06 May 2009 20:37:34 +0000

I love the inclusion of the ‘pass’ statement as well. It just teases the program, letting it see that it is only one statement away from blissfully continuing on in ignorance of all errors. “None shall pass!”

By: Matt Wilson

Matt Wilson — Wed, 06 May 2009 20:02:19 +0000

I don’t know who coined the phrase, but Mike Robellard and I used the phrase “diaper pattern” a lot when we were working on the CRT system.

I still use the phrase today; mostly when I catch way-too-broad except clauses.