Last night I ran into Damian Conway at a speaker’s dinner for this week’s GOTO conference. He’s one of the people I had in mind when I said I enjoy hearing from the Perl community even though I don’t use Perl.

We got to talking about Norris’ number, the amount of code an untrained programmer can write before hitting a brick wall. Damian pointed out that there’s something akin to the Norris’ number for skilled programmers. He said that a few years ago he took this quote from Brian Kernighan to heart:

Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it.

He said he’d realized that he’d written some very complex code that was approaching his level of cleverness and that couldn’t move forward himself, much less get anyone else to take it ownership. “That’s when I decided to dial back the cleverness a bit.”

Related post: Two kinds of software challenges