Re: Help with recursive destructive function

[Eric Abrahamsen]

Michael Heerdegen <address@hidden> writes:

> Eric Abrahamsen <address@hidden> writes:
>
>> How would you feel about gv-ref itself doing a check?
>>
>> (if (and (eq 'closure (caar place))
>>          (eq 'closure (cadr place)))
>>     place
>>   (gv-letplace ...etc...)
>>
>> Too hacky?
>
> `functionp' would probably better, since it's not forbidden to be used
> in dynamically bound Lisp.  Most place expressions will not contain
> something functionp I think.  Using a unique tag would probably be
> cleaner.

I'm conscious of having set out to fix an annoying bug in the Gnus
registry, then moving on to re-write most of eieio-persistent, and now
apparently mucking about in the guts of gv-ref/gv-defer, which three
weeks ago I didn't even know existed. Mission creep is real! Maybe we
should be opening a separate bug report so other people can comment on
adding a unique tag.

> I'm not sure if having `gv-ref-p' would be useful, I can imagine that it
> could, but have myself used this only once or twice.

An intermediate solution could be to write a `gv-ref-p' inline that's
only meant for use with `deep-edit'.

Eric