bug#28302: 26.0.50; [PATCH] Make ucs-names a hash table

[Eli Zaretskii]

> From: Mark Oteiza <mvoteiza@udel.edu>
> Date: Thu, 31 Aug 2017 01:04:15 -0400
> 
> I seem to remember there having been complaints about ucs-names preview
> being slow.  I was curious about how much of that time was spent
> assoc'ing every element of a roughly n = 42k element long alist, and so
> tried making it a hash table instead.  The result is a drastic speedup
> of C-x 8 RET TAB, presumably this makes the operation O(n) vs O(n^2).

Thanks, this is a very good change.  Please make sure (if you haven't
already) that it survives bootstrap.

Also, there are other places which assume that ucs-names is an alist,
so I guess this is not the full final patch?

And this should be mentioned in NEWS under incompatible Lisp changes,
as ucs-names debuted in Emacs 23.1, and there could be some uses of it
outside Emacs proper.