Re: Extending TeX-read-key-val

[Ikumi Keita]

>>>>> Arash Esbati <arash@gnu.org> writes:
>> 2. "KEY-VAL-ALIST can be a symbol or a function call ..."
>> It seems that "function call" is a bit ambiguous to me. How about
>> "KEY-VAL-ALIST can be a variable or a function ..."?

> I wanted to express that something like this would not work:

> (TeX-add-style-hook
>  "foo"
>  (lambda ()
>    (TeX-add-symbols
>     '("bar" (TeX-arg-key-val function-returning-key-val)))))

> If you think your suggestion is more clear, I'm happy to adjust the
> docstring.

Ah, sorry. I didn't understand your code well enough.

>> 1. Maybe 
>> (symbol-value key-val-alist)
>> is more appropriate than
>> (eval key-val-alist t)
>> for its directness.

> I'm not sure if we get into trouble if a globally defvar'ed key-val list
> is let-bound and changed in a function call using `TeX-read-key-val'.
> WDYT?  I haven't checked the occurrence of this within AUCTeX, though.

Do you mean something like this?
----------------------------------------------------------------------
(defvar foo 1)
(defun bar (var)
  (symbol-value var))
(defun xyz ()
  (let ((foo foo))
    (setq foo (1+ foo))
    (bar 'foo)))
(xyz) ; => 2
foo ; => 1
----------------------------------------------------------------------
As Tassilo pointed out, my understanding is that:
- Once a variable is marked as special by defvar, its binding is
  always dynamic scoped even with `let'.
- Thus `symbol-value' returns its temporal value bound by `let' for such
  variable.
I think the result of the above example supports this view.

Regards,
Ikumi Keita