Re: master af4791b5706: Fix apparently wrong `delete` and `delq` value discards (bug#61730)

[Mattias Engdegård]

25 maj 2023 kl. 09.09 skrev Eli Zaretskii <eliz@gnu.org>:

> configvar-name is evidently a string, whereas the value returned by
> delq is not a string at all.  Do you understand why this code even
> calls delq?

I thought I did but may have been mistaken. Let's look at this again:

From the text of this function we can infer that `configvar-name` is the name 
(symbol) of a dynamic variable whose value is a list of symbols naming other 
variables. If we strip all the `boundp` and `delq` gunk, this function 
essentially becomes

  (mapcar #'symbol-value (symbol-value configvar-name))

I don't fancy mutation of a list while it's being looped over any more than you 
do, but I didn't want to touch it more than strictly necessary.

>  If it wants to change the value of configvar-name, it
> should assign to (symbol-value configvar-name), no?

It does.

>  And if all it
> wants is to skip 'sym' and not add it to 'got', then there's no need
> to call delq, right?

As the yes-or-no-p call suggests, the intent is likely to remove unbound 
entries permanently so there is no need to ask again in future calls, or ask 
more than once for the same variable appearing in duplicate during the same 
call.