Re: master c5cf630: Don't clobber match data in utf-8-hfs conversion (bug#41445)

[Stefan Monnier]

>> 1- document that `(en|de)code-coding-string` preserve the match-data.
>> 2- document in `define-coding-system` that the pre/post-conversion
>>   functions should preserve the match-data.
>
> Very reasonable; now done on master.
> We could perhaps say the same thing about {en,de}code-coding-region but
> I didn't do that in this change.

`(en|de)code-coding-region` run various other (buffer-modification)
hooks, so I don't think anyone currently relies on them preserving the
match-data (and it would be a wrong assumption), also because those
function can change buffer positions making the match-data invalid even
if it's not modified.  So I don't see any need to declare that those
functions preserve the match-data.


        Stefan