Re: WIP: lookbehind constraints for our regexp engine

On Friday, October 16, 2015, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

>
> Anyway, I'm not planning to do much more work on this right now, but
> I thought I'd throw it out there just to let people know that this seems
> within reach. I'm curious to know how many people care, and how much.
>
>
+1

It's hard to quantify how much but look behind is a tool that I find
occasion to use. My most recent need involved ensuring that the current
position after processing two variable length matches is exactly n
characters from the start of the string.

I don't have any immediate projects that would be refactored into a more
pure SQL variation for having this feature so on that the strength is
fairly low. But if you are going to do it then now, while it is fresh,
would be the best time.

David J.