Subject: bug#77924: 31.0.50; [Feature branch] Change marker implementation

From: Stefan Monnier <[email-masked]>
Date: Fri, 25 Apr 2025 15:02:01 -0400

> Assume we initially are position P, and the next index
> entry > P is I0 and so on.
>
>    -----P---------I0-----------I1.....
>
> After insertion at P, the index is invalidated
>
>    -----P------------------------.....
>
> Someone asks for a position P2 < I0, index is built up to
> I0. If P2 > I0 then more.

Yes, but in the worst case we're still talking about
invalidating+recomputing one interval per line.  So my O(1) would be
around 4096B / ~50B/line so less than 100.
I think refilling the whole index 100 times should still take
significantly less time than the rest of the indentation code.

        Stefan