Re: [PATCH] [Outreachy] git/userdiff.c fix regex pattern error

From: Ananya Krishna Maram <ananyakittu1997@gmail.com>
To: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Cc: Christian Couder <christian.couder@gmail.com>, git@vger.kernel.org
Subject: Re: [PATCH] [Outreachy] git/userdiff.c fix regex pattern error
Date: Thu, 4 Oct 2018 15:05:18 +0530	[thread overview]
Message-ID: <CA+=o6KFN-p901GiJzj5BquU2RKCVTOKarGpjjuqsASN_uqGZSQ@mail.gmail.com> (raw)
In-Reply-To: <nycvar.QRO.7.76.6.1810041624290.73@tvgsbejvaqbjf.bet>

On Thu, 4 Oct 2018 at 19:56, Johannes Schindelin
<Johannes.Schindelin@gmx.de> wrote:
>
> Hi Ananya,
>
> thank you for taking the time to write this patch!
>
> On Thu, 4 Oct 2018, Ananya Krishna Maram wrote:
>
> > the forward slash character should be escaped with backslash. Fix
> > Unescaped forward slash error in Python regex statements.
> >
> > Signed-off-by: Ananya Krishna Maram<ananyakittu1997@gmail.com>
>
> That explains pretty well what you did, but I wonder why the forward slash
> needs to be escaped? I would understand if we enclosed the pattern in
> `/<regex>/`, as it is done e.g. in Javascript, but we do not...

You are correct, the code would execute either ways. But when I came across
this line, I didn't get it's meaning instantly because as per standards, forward
slash has to be escaped. In fact when open source code is written according to
standards, the code will be reachable to more people.

Thanks,
Ananya.

> Thanks,
> Johannes
>
> > ---
> >  userdiff.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/userdiff.c b/userdiff.c
> > index f565f6731..f4ff9b9e5 100644
> > --- a/userdiff.c
> > +++ b/userdiff.c
> > @@ -123,7 +123,7 @@ PATTERNS("python", "^[ \t]*((class|def)[ \t].*)$",
> >        /* -- */
> >        "[a-zA-Z_][a-zA-Z0-9_]*"
> >        "|[-+0-9.e]+[jJlL]?|0[xX]?[0-9a-fA-F]+[lL]?"
> > -      "|[-+*/<>%&^|=!]=|//=?|<<=?|>>=?|\\*\\*=?"),
> > +      "|[-+*\/<>%&^|=!]=|\/\/=?|<<=?|>>=?|\\*\\*=?"),
> >        /* -- */
> >  PATTERNS("ruby", "^[ \t]*((class|module|def)[ \t].*)$",
> >        /* -- */
> > --
> > 2.17.1
> >
> >