Re: `gnus-bound-and-true-p'

[Robert Pluim <rpluim@gmail.com>]

Reiner Steib <reinersteib+gmane@imap.cc> writes:

> On Tue, Nov 01 2011, Ted Zlatanov wrote:
>> -(eval-when-compile
>> -  ;; This is unnecessary in the compiled version as it is a macro.
>> -  (if (fboundp 'bound-and-true-p)
>> -      (defalias 'gnus-bound-and-true-p 'bound-and-true-p)
>> -    (defmacro gnus-bound-and-true-p (var)
>> -      "Return the value of symbol VAR if it is bound, else nil."
>> -      `(and (boundp (quote ,var)) ,var))))
>> -
>> -(defun gnus-bound-and-true-dumber-p (sym)
>> +;; simple check, can be a macro but this way, although slow, it's really clear
>> +(defun gnus-bound-and-true-p (sym)
>>    (and (boundp sym) (symbol-value sym)))
>
> On Wed, Nov 02 2011, Ted Zlatanov wrote:
>> -;; simple check, can be a macro but this way, although slow, it's really clear
>> +;; Simple check: can be a macro but this way, although slow, it's really clear.
>> +;; We don't use `bound-and-true-p' because it's not in XEmacs.
>>  (defun gnus-bound-and-true-p (sym)
>>    (and (boundp sym) (symbol-value sym)))
>
> Can't you use an alias for Emacs and a macro for XEmacs?
>
> (if (fboundp 'bound-and-true-p)
>     (defalias 'gnus-bound-and-true-p 'bound-and-true-p)
>   (defmacro gnus-bound-and-true-p (var)
>     "Return the value of symbol VAR if it is bound, else nil."
>     `(and (boundp (quote ,var)) ,var)))

Especially since in XEmacs 21.5:

`bound-and-true-p' is a compiled Lisp macro
  -- loaded from "/build/xemacs-edge/lisp/subr.elc"
(bound-and-true-p VAR)

Documentation:
Return the value of symbol VAR if it is bound, else nil.

And:

(fboundp 'bound-and-true-p) => t

Robert