Klaus Straubinger wrote:
> Kevin Rodgers <[EMAIL PROTECTED]> wrote:
>>How exactly is that improvement implemented?
>>
>>(cons redirect-uri url-callback-arguments)
>>
>>(if url-callback-arguments
>> (cons redirect-uri (cdr url-callback-arguments))
>> (list redirect-uri))
>
> I chose something like the second alternative:
>
> (if url-callback-arguments
> (setcar url-callback-arguments redirect-uri)
> (setq url-callback-arguments (list redirect-uri)))
Is it necessary to destructively modify url-callback-arguments? I.e.
is it used elsewhere that must reflect the redirection as well?
Note that setcar does not return the modified cons, so I think that
should be (asssuming setcar is indeed necessary):
(if url-callback-arguments
(progn
(setcar url-callback-arguments redirect-uri)
url-callback-arguments)
(setq url-callback-arguments (list redirect-uri)))
> The first would not be correct because the URL sometimes already
> present as first argument in the url-callback-arguments list must be
> replaced.
Again: destructively, or just in this particular call to url-retrieve?
> Would it work then to simply write
>
> (setq url-callback-arguments
> (append (list redirect-uri) (cdr url-callback-arguments)))
>
> independent of the value of url-callback-arguments?
Yes, it's not necessary to test url-callback-arguments and it's better
to avoid destructive operations on lists unless you're sure of what
you're doing.
But (append (list x) ...) is better expressed as (cons x ...):
(cons redirect-uri (cdr url-callback-arguments))
Again, why setq? Do you really need to change its global value?
--
Kevin Rodgers
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