Re: TeX-arg-key-val syntax and let go of eval

[Arash Esbati]

Hi Tassilo,

Tassilo Horn <tsdh@gnu.org> writes:

> Arash Esbati <arash@gnu.org> writes:
>
>>> So what's wrong with this one?
>>>
>>> (TeX-add-style-hook
>>>  "foo"
>>>  (lambda ()
>>>    (TeX-add-symbols
>>>     `("bar" (TeX-arg-key-val
>>>              ,(lambda ()
>>>                (append (func1-returning-keyval-alist)
>>>                        (func2-returning-keyval-alist))))))))
>>
>> If this is the best/only option, well, I'm buying it :)
>
> It's the typical lispy solution which doesn't require eval.
>
>>> That's again caught by the functionp case and can simply be
>>> funcalled.
>>
>> How would you then re-write `TeX-read-key-val'?
>
> In my suggested version where (TeX-arg-key-val foo) would funcall foo if
> it were a function (without having to wrap it in parentheses), it would
> be:
>
> (defun TeX-read-key-val (optional key-val-alist &optional prompt)
>   (multi-prompt-key-value
>    (TeX-argument-prompt optional prompt "Options (k=v)")
>    (cond ((and (functionp key-val-alist)
>                (fboundp key-val-alist))
>           (funcall key-val-alist))
>          ((and (symbolp key-val-alist)
>                (boundp key-val-alist))
>           (symbol-value key-val-alist))
>          ((and (listp key-val-alist)
>                (listp (car key-val-alist)))
>           key-val-alist)
>          (t (error "Cannot interpret key-val-alist %S" key-val-alist)))))

Sorry for my late response.  I started changing `TeX-read-key-val' and
our styles acc. to discussion above and I think we're still not there.
In the example above,

  (TeX-add-style-hook
   "foo"
   (lambda ()
     (TeX-add-symbols
      `("bar" (TeX-arg-key-val
               ,(lambda ()
                  (append (func1-returning-keyval-alist)
                          (func2-returning-keyval-alist))))))))

the part ",(lambda () (append ..." is turned into a

  "(closure (t) nil (append ..."

and then the `fboundp' check in `TeX-read-key-val' gets upset.  I
suggest to write `TeX-read-key-val' like this:

(defun TeX-read-key-val (optional key-val-alist &optional prompt)
  (multi-prompt-key-value
   (TeX-argument-prompt optional prompt "Options (k=v)")
   (cond ((or (and (symbolp key-val-alist)
                   (fboundp key-val-alist))
              (functionp key-val-alist))
          (funcall key-val-alist))
         ((and (symbolp key-val-alist)
               (boundp key-val-alist))
          (symbol-value key-val-alist))
         ((and (listp key-val-alist)
               (listp (car key-val-alist)))
          key-val-alist)
         (t (error "Cannot interpret key-val-alist %S" key-val-alist)))))

WDYT?

>> And while we're at, what do we do with `TeX-arg-eval'?
>
> Nothing.

Ok.

Best, Arash