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* bug#14935: 24.3.50; pcase (or) UPAT fails?
@ 2013-07-23 11:30 Vitalie Spinu
  2013-07-23 12:08 ` Andreas Schwab
  2013-07-23 13:44 ` Stefan Monnier
  0 siblings, 2 replies; 6+ messages in thread
From: Vitalie Spinu @ 2013-07-23 11:30 UTC (permalink / raw)
  To: 14935


Is this a bug?


This works:

(pcase (list 23 nil "%")
  (`(,scale nil "%") (message "%s" scale))
  (_ (message "failed")))


This doesn't:

(pcase (list 23 nil "%")
  (`(,scale nil (or "^" "%")) (message "%s" scale))
  (_ (message "failed")))


Thanks, 

    Vitalie




In GNU Emacs 24.3.50.7 (i686-pc-linux-gnu, X toolkit, Xaw scroll bars)
 of 2013-07-19 on vitoshka-OptiPlex-745
Windowing system distributor `The X.Org Foundation', version 11.0.11303000
System Description:	Ubuntu 13.04





^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#14935: 24.3.50; pcase (or) UPAT fails?
  2013-07-23 11:30 bug#14935: 24.3.50; pcase (or) UPAT fails? Vitalie Spinu
@ 2013-07-23 12:08 ` Andreas Schwab
  2013-07-23 13:44 ` Stefan Monnier
  1 sibling, 0 replies; 6+ messages in thread
From: Andreas Schwab @ 2013-07-23 12:08 UTC (permalink / raw)
  To: Vitalie Spinu; +Cc: 14935

Vitalie Spinu <spinuvit@gmail.com> writes:

> (pcase (list 23 nil "%")
>   (`(,scale nil (or "^" "%")) (message "%s" scale))
>   (_ (message "failed")))

If you want to embed a UPattern in a QPattern you have to prefix it with
a comma, like you did with `scale'.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."





^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#14935: 24.3.50; pcase (or) UPAT fails?
  2013-07-23 11:30 bug#14935: 24.3.50; pcase (or) UPAT fails? Vitalie Spinu
  2013-07-23 12:08 ` Andreas Schwab
@ 2013-07-23 13:44 ` Stefan Monnier
  2013-07-23 21:00   ` Vitalie Spinu
  1 sibling, 1 reply; 6+ messages in thread
From: Stefan Monnier @ 2013-07-23 13:44 UTC (permalink / raw)
  To: Vitalie Spinu; +Cc: 14935-done

> This doesn't:

> (pcase (list 23 nil "%")
>   (`(,scale nil (or "^" "%")) (message "%s" scale))
>   (_ (message "failed")))

> Is this a bug?

No, it's normal.  The third pattern matches a list of 3 elements (the
first being the symbol `or').  You probably meant to do

   (pcase (list 23 nil "%")
     (`(,scale nil ,(or `"^" `"%")) (message "%s" scale))
     (_ (message "failed")))


-- Stefan





^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#14935: 24.3.50; pcase (or) UPAT fails?
  2013-07-23 13:44 ` Stefan Monnier
@ 2013-07-23 21:00   ` Vitalie Spinu
  2013-07-24  5:14     ` Stefan Monnier
  0 siblings, 1 reply; 6+ messages in thread
From: Vitalie Spinu @ 2013-07-23 21:00 UTC (permalink / raw)
  To: 14935


Thanks Andreas and Stephen, 

I actually tried unquoting with comma before reporting. But it never
occurred to me that strings should be backticked. Strings are selfquoted
and, in my understanding, the following should have worked:

   (pcase "^" 
     ((or "^" "%") (message "here")))


The documentation says that strings are UPATs so 

   (pcase "^" 
     ("^" (message "here")))

works. Then docs also say that (or UPAT UPAT) is also an UPAT so (or "^"
"%") should also work. Do I miss anything?

Thanks, 

    Vitalie

 >> Stefan Monnier <monnier@iro.umontreal.ca>
 >> on Tue, 23 Jul 2013 09:44:49 -0400 wrote:

 >> This doesn't:
 >> (pcase (list 23 nil "%")
 >> (`(,scale nil (or "^" "%")) (message "%s" scale))
 >> (_ (message "failed")))

 >> Is this a bug?

 > No, it's normal.  The third pattern matches a list of 3 elements (the
 > first being the symbol `or').  You probably meant to do

 >    (pcase (list 23 nil "%")
 >      (`(,scale nil ,(or `"^" `"%")) (message "%s" scale))
 >      (_ (message "failed")))

 > -- Stefan






^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#14935: 24.3.50; pcase (or) UPAT fails?
  2013-07-23 21:00   ` Vitalie Spinu
@ 2013-07-24  5:14     ` Stefan Monnier
  2013-07-24  7:19       ` Vitalie Spinu
  0 siblings, 1 reply; 6+ messages in thread
From: Stefan Monnier @ 2013-07-24  5:14 UTC (permalink / raw)
  To: Vitalie Spinu; +Cc: 14935-done

>    (pcase "^" 
>      ((or "^" "%") (message "here")))

Yes, this should work, but it incorrectly used `memq' whereas the (or
`"^" `"%") pattern correctly leads to the use of `member'.

I installed the patch below which should fix it,


        Stefan


=== modified file 'lisp/emacs-lisp/pcase.el'
--- lisp/emacs-lisp/pcase.el	2013-07-08 21:54:54 +0000
+++ lisp/emacs-lisp/pcase.el	2013-07-24 05:10:31 +0000
@@ -659,7 +659,11 @@
               (memq-fine t))
           (when all
             (dolist (alt (cdr upat))
-              (unless (or (pcase--self-quoting-p alt)
+              (unless (if (pcase--self-quoting-p alt)
+                          (progn
+                            (unless (or (symbolp alt) (integerp alt))
+                              (setq memq-fine nil))
+                            t)
                           (and (eq (car-safe alt) '\`)
                                (or (symbolp (cadr alt)) (integerp (cadr alt))
                                    (setq memq-fine nil)






^ permalink raw reply	[flat|nested] 6+ messages in thread

* bug#14935: 24.3.50; pcase (or) UPAT fails?
  2013-07-24  5:14     ` Stefan Monnier
@ 2013-07-24  7:19       ` Vitalie Spinu
  0 siblings, 0 replies; 6+ messages in thread
From: Vitalie Spinu @ 2013-07-24  7:19 UTC (permalink / raw)
  To: Stefan Monnier; +Cc: 14935-done


Thanks, it works. And more complex patterns are also fine now:

   (pcase (list 23 nil "%")
     (`(,x nil ,(or "^" "%")) (message "%s" x)))


 >> Stefan Monnier <monnier@iro.umontreal.ca>
 >> on Wed, 24 Jul 2013 01:14:10 -0400 wrote:

 >> (pcase "^" 
 >> ((or "^" "%") (message "here")))

 > Yes, this should work, but it incorrectly used `memq' whereas the (or
 > `"^" `"%") pattern correctly leads to the use of `member'.

 > I installed the patch below which should fix it,

 >         Stefan

 > === modified file 'lisp/emacs-lisp/pcase.el'
 > --- lisp/emacs-lisp/pcase.el	2013-07-08 21:54:54 +0000
 > +++ lisp/emacs-lisp/pcase.el	2013-07-24 05:10:31 +0000
 > @@ -659,7 +659,11 @@
 >                (memq-fine t))
 >            (when all
 >              (dolist (alt (cdr upat))
 > -              (unless (or (pcase--self-quoting-p alt)
 > +              (unless (if (pcase--self-quoting-p alt)
 > +                          (progn
 > +                            (unless (or (symbolp alt) (integerp alt))
 > +                              (setq memq-fine nil))
 > +                            t)
 >                            (and (eq (car-safe alt) '\`)
 >                                 (or (symbolp (cadr alt)) (integerp (cadr alt))
 >                                     (setq memq-fine nil)






^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2013-07-24  7:19 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-07-23 11:30 bug#14935: 24.3.50; pcase (or) UPAT fails? Vitalie Spinu
2013-07-23 12:08 ` Andreas Schwab
2013-07-23 13:44 ` Stefan Monnier
2013-07-23 21:00   ` Vitalie Spinu
2013-07-24  5:14     ` Stefan Monnier
2013-07-24  7:19       ` Vitalie Spinu

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