bug#63861: [PATCH] pp.el: New "pretty printing" code

[Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

> `pp-region`s performance is not quite linear in the size of the file :-(
> Interestingly, the same holds for `tv/pp-region`:
>
>       77101B /   4.62344853s  = 16676 B/s
>      163258B /  13.237991019s = 12332 B/s
>     1125154B / 235.134082197s =  4785 B/s
>
> even though it works in a fundamentally very different way (which, to
> my naive eye should result in a linear performance), so maybe the
> slowdown here is due to something external (such as the fact that
> various operations on buffers get slower as the buffer gets bigger).

I think I figured it out: the larger files happen to have relatively
more (smaller) "objects".  So it is more or less linear, just not in the
size in bytes but in the size in number of objects.


        Stefan