@TristonianJones Curious how you feel about this.

I don't like having to add interpretable nodes here, but that's the existing mechanism so I kept the pattern. Maybe an alternative in the future would be to have a program wide pre|post eval chain that we could put checks like this in.

@jpbetz In most cases, the halting checks should be isolated to comprehension loops where it's possible to evaluate for a significant period of time. My thought had been to provide a decorator which only affects the evalFold operation. The idea would be similar though. I'll look it over in more detail tomorrow.

I've limited the decoration to the step eval of a fold, I discovered that this requires a panic to early exit because the fold continues to evaluate after the step op returns an error. I don't have a strong opinion on if we should avoid a panic here or not.

I'm going to close this in favor of #502