Jim Bob wrote:

> So, how'd it get there? Is there some killer use for callcc that I'm
> missing? Was it just for the "gee whiz" factor?

I'd be interested to read about some real-world examples where people have used callcc, not just to try it out, but because it was the "right" way to do something (for efficiency, or code brevity or whatever reason).

So, as opposed to the examples we find on some of the Ruby web pages, which are, as Bob said, effectively tutorials on how one *might* use callcc, can someone give us some examples of production code they've written that uses continuations?