Kevin Bourrillion on Type Safety

I was reading Kevin Bourrillion’s blog today. Kevin is a senior software engineer at Google, and is working with “Crazy” Bob Lee on Guice, Google’s internal dependency injection framework that they recently released into the wild. (I’m interested in Guice for my own reasons, which will become apparent soon.

Anyhow, Kevin has a post where he explains what “extraordinarily type-safe” is to his wife. In it, he provides the one of the best takes on type safety that I’ve ever read:

When things are not “typesafe”, someone can walk up to you and ask for your credit card and you can hand him a font, and he’ll say, “30 seconds.” And he’ll walk away, many kilograms away and only later will he gleefully try to charge your credit card and explode cosmically. You know, like what was supposed to happen in Ghostbusters when they crossed the streams.

Freakin’ fantastic. Any time someone tries to sell me on the idea that weak-typing is better because it saves developer cycles, I’ll have to point them to that article.