Hi,

I'm not sure this was emphasized enough, so I'm adding my two cents there.

Before the generators, typed or conditional catches were not really essential. Barely some edge cases needed to use try/catch in JS code.

With generators however, try/catch become the only sane way to handle errors. It was shown in this thread before why. And as they currently stand, they are in no way satisfying enough for generators in production code, except with some boilerplate. This boilerplate would be easily skipped by implemented conditional catches, as Firefox already implements.

What's stopping people from adding conditional catches in the ES6 proposal?

W.r.t the pattern matching, concerning this issue, it looks like we're trying to use a nuclear cannon when a knife would be enough.

Am I off somewhere? I may very well be, but it sounds like