Re: [bug-gawk] gawk array problem

[Aharon Robbins]

Hi.

David's answer is indeed correct.  Thanks to Ludek for sending in the bug
report, and thanks to David for answering.

Arnold

> Date: Wed, 6 Apr 2016 13:57:30 -0700
> From: david kerns <address@hidden>
> To: Ludek Bican <address@hidden>
> Cc: address@hidden
> Subject: Re: [bug-gawk] gawk array problem
>
> change:
>
> /del/ && M[$2] { delete M[$2]; print "-- "$2 }
>
> to
>
> /del/ && ($2 in M) { delete M[$2]; print "-- "$2 }
>
> you were creating M["3"]=0, which is false
>
>
> On Wed, Apr 6, 2016 at 12:01 PM, Ludek Bican <address@hidden> wrote:
>
> > Hi,
> >
> >  there is some problem with arrays
> >
> > Regards,
> >
> > Ludek
> > email: address@hidden
> >
> > ---------------------------------------------
> >
> > $ uname -a
> > Linux ub1 3.13.0-63-generic #103-Ubuntu SMP Fri Aug 14 21:42:59 UTC 2015
> > x86_64 x86_64 x86_64 GNU/Linux
> >
> > $ awk --ver | head -1
> > GNU Awk 4.0.1
> >
> > $ dpkg -l gawk | tail -2  | cut -c 1-60
> > +++-====================-==========================-====
> > ii  gawk
> > 1:4.0.1+dfsg-2.1ubuntu2                             amd6
> >
> > ----------------------------------------
> > $ cat 1.txt
> > add  1
> > add  2
> > del 3
> > del 1
> > ---------------------------------------
> > $ awk '
> >   /add/ { M[$2]++; print "++ "$2 }
> >   /del/ && M[$2] { delete M[$2]; print "-- "$2 }
> >   END { for (I in M) print "stay "I }
> > ' 1.txt
> > --------------------------------------
> > ==== output:
> > ++ 1
> > ++ 2
> > -- 1
> > stay 2
> > stay 3    # ???????
> >
> >
> >
> >