Re: How to debug modification to a variable value?

[Tassilo Horn]

"Drew Adams" <address@hidden> writes:

>> I also removed all destructive function calls in there, although it
>> operates only on a list created by `mapcar', and that's a copy
>> anyway, right?
>
> It's a top-level copy only. That is, each element in the original list
> is processed by the function arg, and the results are consed up to
> produce a new list.

I see.  But the only destructive functions I used are `nconc' and `delq'
(to filter nil values), and those operate on a list produced with `cons'
and `list' only on basic values.  And when the problem appeared, I
changed those calls to `append' and `remove' and re-evaled the function
definition (*), but the problem persisted.

And another thing which is a bit puzzling: I used that mode for month,
and till yesterday it never occured.  If it was a problem with
destructive functions, shouldn't it occur every time?

The main question still stands: is it possible to debug the modification
of a variable's value?  That would also find the place in the code where
a destructive function causes harm.

Bye,
Tassilo

(*) Maybe I forgot the re-evaluation?  Well, I'll see if it occurs
again...