In the presentation it was two if's, not an if and an elif. Someone up-thread misrepresented it.

I didn't read it carefully here, as I had already seen the presentation and it wasn't until your disagreement I realized the code was different.

Yup... my comment about "detracting from the point" was about such an important semantic change to slip through unnoticed. (not about the points delivered in the talk itself or anything)

There's nothing wrong with if/elses, but I strongly prefer pattern matching, where available. And even more, I think it's important to keep computation and presentation separate... that is, to not entagle IO with the rest of the code.

(Unfortunately Haskell is the only language I know of that gives you a tool to tackle that)

Obviously this was just a small example, but I've seen unintended IO byte back the developer in real world (Python) code.

And another small comment: since I haven't bothered to comment on Hettinger's talk before now.

I liked it (but played it back at 1.5x)... but since it's not first talk by Raymond Hettinger I saw, I knew that his delivery is good. Some of the stuff (should?) be obvious to every (Python) developer (but repetita juvant). I didn't like the jab at Java for the mistake of iterating over indexes: there's no excuse to writing that code not even there (look at the Iterator and Iterable interfaces)

That's not his code.