Macro aborts even though regexp instance exists

Macro aborts even though regexp instance exists

[Swami Tota Ram Shankar]

Hi emacs users,

I write a simple macro which works, however, it fails in a particular
case.

C-s
M-r

to get into isearch-forward-regexp

and give a regexp like

ONE\|TWO

It works for every TWO and ONE as long as there is a ONE ahead of TWO.
In the last instance, no ONE exists after TWO and it fails.

\| <=> OR or disjunction.

Any solutions?

This is such a fundamental issue that I think its a bug. When the C-s
M-r  is used outside the macro definition, the cursor gladly returns
to the original position when OR is entered and proceeds forward from
there, but perhaps, the macro aborts.

I guess, this can lead to a lot of confusion and time wastage, if the
user is unaware of this and most likely to neglect it because its
contrary to normal usage.

Re: Macro aborts even though regexp instance exists

[Stefan Monnier]

> Hi emacs users,
> I write a simple macro which works, however, it fails in a particular case.
> C-s M-r
> to get into isearch-forward-regexp
> and give a regexp like ONE\|TWO
> It works for every TWO and ONE as long as there is a ONE ahead of TWO.
> In the last instance, no ONE exists after TWO and it fails.
[...]
> to the original position when OR is entered and proceeds forward from
> there, but perhaps, the macro aborts.

Indeed, that's a problem: the macro aborts because macros abort not only
on error but also when `ding' is called.

> Any solutions?

You can work around the problem in this particular case as follows:
first do C-s M-r ONE\|TWO RET, and then record your macro using C-u C-s
C-s to recall the last regexp used, so it gets inserted "all at once"
without going through the problematic intermediate state (which is not
when it gets to \ but rather when it gets to ON or ONE and it doesn't
match anything).  Maybe isearch-search shouldn't call ding when the
match fails and we're matching regexps (and the match failed because of
a new char being added to search regexp, rather than because the user
hit C-s to jump to the next match).

Please M-x report-emacs-bug,


        Stefan

bug#12722: Macro aborts even though regexp instance exists

[Andreas Schwab]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

> You can work around the problem in this particular case as follows:
> first do C-s M-r ONE\|TWO RET, and then record your macro using C-u C-s
> C-s to recall the last regexp used,

Another workaround is to put \( \) around it so that the regexp isn't
complete until the closing paren.

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."

bug#12722: Macro aborts even though regexp instance exists

[Glenn Morris]

Here we see yet another instance why the newsgroup interface should not
be used for bug reports. None of the context is visible in

http://debbugs.gnu.org/12722

I'm not tidying it up.

Also, things should not be triple posted to gnu.emacs.help, comp.emacs,
and gnu.emacs.bug. From the help-gnu-emacs list description:
  "Please don't send bug reports here, or to the comp.emacs newsgroup;"