Re: [Emacs-diffs] master bc2a93d: Fix more regular expression typos

Re: [Emacs-diffs] master bc2a93d: Fix more regular expression typos

[Stefan Monnier]

> diff --git a/lisp/pcomplete.el b/lisp/pcomplete.el
> index d4ee2c3..ef285db 100644
> --- a/lisp/pcomplete.el
> +++ b/lisp/pcomplete.el
> @@ -768,7 +768,7 @@ this is `comint-dynamic-complete-functions'."
>  	(push (point) begins)
>          (while
>              (progn
> -              (skip-chars-forward "^ \t\n\\")
> +              (skip-chars-forward "^ \t\n")
>                (when (eq (char-after) ?\\)
>                  (forward-char 1)
>                  (unless (eolp)

Hmm... no this needs to be 

    (skip-chars-forward "^ \t\n\\")
or
    (skip-chars-forward "^ \t\n\\\\")


-- Stefan "who happened to look at it right now"

Re: [Emacs-diffs] master bc2a93d: Fix more regular expression typos

[Mattias Engdegård]

20 mars 2019 kl. 13.26 skrev Stefan Monnier <monnier@iro.umontreal.ca>:
> 
>>             (progn
>> -              (skip-chars-forward "^ \t\n\\")
>> +              (skip-chars-forward "^ \t\n")
>>               (when (eq (char-after) ?\\)
>>                 (forward-char 1)
>>                 (unless (eolp)
> 
> Hmm... no this needs to be 
> 
>    (skip-chars-forward "^ \t\n\\")
> or
>    (skip-chars-forward "^ \t\n\\\\")

Are you sure? Trailing backslashes in skip-sets have no effect, and semantically the backslash cannot reasonably be included because of the condition that follows.

Re: [Emacs-diffs] master bc2a93d: Fix more regular expression typos

[Stefan Monnier]

>>>             (progn
>>> -              (skip-chars-forward "^ \t\n\\")
>>> +              (skip-chars-forward "^ \t\n")
>>>               (when (eq (char-after) ?\\)
>>>                 (forward-char 1)
>>>                 (unless (eolp)
>> 
>> Hmm... no this needs to be 
[...]
> Are you sure? Trailing backslashes in skip-sets have no effect, and
> semantically the backslash cannot reasonably be included because of the
> condition that follows.

Notice it's a negated skip, so with (skip-chars-forward "^ \t\n") we'll
happily skip over a backslash, and hence the subsequent (eq (char-after) ?\\)
can never be true.

The skip+when do the equivalent of a regexp "[^ \t\n\\]\\|\\\\.".


        Stefan

Re: [Emacs-diffs] master bc2a93d: Fix more regular expression typos

[Mattias Engdegård]

20 mars 2019 kl. 14.14 skrev Stefan Monnier <monnier@iro.umontreal.ca>:
> 
> Notice it's a negated skip, so with (skip-chars-forward "^ \t\n") we'll
> happily skip over a backslash, and hence the subsequent (eq (char-after) ?\\)
> can never be true.

Sorry, you are right -- I didn't notice the negation. The "\\\\" should be included.

Re: [Emacs-diffs] master bc2a93d: Fix more regular expression typos

[Paul Eggert]

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On 3/20/19 6:33 AM, Mattias Engdegård wrote:
> The "\\\\" should be included.

Thanks to both of you. I installed the attached.


[-- Attachment #2: 0001-Fix-pcomplete-typo-in-recent-regex-typo-fix.patch --]
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From 8c30a1c51214058f28014953fc5b23d3cf9e3826 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Wed, 20 Mar 2019 09:23:05 -0700
Subject: [PATCH] Fix pcomplete typo in recent regex typo fix

Problem reported by Stefan Monnier in:
https://lists.gnu.org/r/emacs-devel/2019-03/msg00682.html
* lisp/pcomplete.el (pcomplete-parse-comint-arguments):
Restore the trailing backslash (but two of them this time).
---
 lisp/pcomplete.el | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lisp/pcomplete.el b/lisp/pcomplete.el
index ef285db57e..d0f2a2e24d 100644
--- a/lisp/pcomplete.el
+++ b/lisp/pcomplete.el
@@ -768,7 +768,7 @@ pcomplete-parse-comint-arguments
 	(push (point) begins)
         (while
             (progn
-              (skip-chars-forward "^ \t\n")
+              (skip-chars-forward "^ \t\n\\\\")
               (when (eq (char-after) ?\\)
                 (forward-char 1)
                 (unless (eolp)
-- 
2.20.1