Shouldn't that *.** be *.*? *to avoid having it consume everything?
On Sun, Dec 23, 2012 at 10:01 AM, Ken Slater <kenslate...@gmail.com> wrote:
> On Sun, Dec 23, 2012 at 8:27 AM, punit jain <contactpunitj...@gmail.com>
> wrote:
> > Hi,
> >
> > I am doing grouping but seeing some weird behavior :-
> >
> > the strings in a file are like :-
> > AccessModes =
> >
> (18,Mail,POP,IMAP,PWD,WebMail,WebSite,Relay,Mobile,FTP,MAPI,TLS,LDAP,WebCAL);
> > ....
> > ...
> > .
> > multiple lines
> >
> > I am seeing which lines have both POP and Webmail as below :-
> >
> > if( $line =~ /AccessModes\s*=\s*.*(WebMail)*.*(POP).*(WebMail)*.*/ ) {
> > if(defined $2) {
> > print "$2 $1"."$line"."\n";
> > }
> > }
> >
> >
> > However I get these below :-
> >
> > POPUse of uninitialized value in concatenation (.) or string at
> > test.plline 283, <GEN85> line 2.
> > POPUse of uninitialized value in concatenation (.) or string at
> > test.plline 283, <GEN86> line 2.
> > POPUse of uninitialized value in concatenation (.) or string at
> > test.plline 283, <GEN87> line 2.
> >
> > Any clue why ?
> >
> > Regards.
>
> Hi,
> Your basic mistake is making the WebMail strings you are searching for
> optional by having an asterisk (*) following them. This means zero or
> more instances of the strings. Thus once it matches POP, it is quite
> happy to match zero instances of WebMail. I included some code below
> to demonstrate:
>
> use strict;
> use warnings;
> use Data::Dumper;
>
> my @regExps = (
> # Original
> qr/AccessModes\s*=\s*.*(WebMail)*.*(POP).*(WebMail)*.*/,
> # Here we make the second WebMail non-optional
> (removed following *)
> # so it will match POP with a WebMail later on the line
> qr/AccessModes #literal match
> \s* # optionasl whitespace
> = # literal equal sign
> \s* # optional whitespace
> .* # match as many characters
> (WebMail)* # literal WebMail, but this is optional
> # Therefore, it is skipped if POP is found
> first
> .* # match as many characters as we can
> (POP) # match literal POP
> .* # match as many characters as we can
> # until we see WebMail
> (WebMail) # match literal WebMail
> /x,
> # Make the matches non-optional and check for both strings
> # at the same time using 'or' (|).
> # This is probably the method you want to use.
> qr/AccessModes #literal match
> \s* # optionasl whitespace
> = # literal equal sign
> \s* # optional whitespace
> .* # match as many characters as we can
> # until we find WebMail or POP
> (WebMail|POP) # literal WebMail or POP
> .* # match as many characters as we can
> # non-greedily, so it will match second
> # occurence
> (WebMail|POP) # literal WebMail or POP
> /x
> );
>
> while (my $line = <DATA>) {
> print $line;
> for my $re ( @regExps ) {
> print " RE: $re\n";
> if( $line =~ /$re/) {
> print " 1: >$1<\n" if defined($1);
> print " 2: >$2<\n" if defined($2);
> print " 3: >$3<\n" if defined($3);
> }
> }
> }
>
> __DATA__
> AccessModes = (POP);
> AccessModes =
> (18,Mail,POP,IMAP,PWD,WebMail,WebSite,Relay,Mobile,FTP,MAPI,TLS,LDAP,WebCAL);
> AccessModes =
> (18,Mail,IMAP,PWD,WebMail,WebSite,POP,Relay,Mobile,FTP,MAPI,TLS,LDAP,WebCAL);
>
>
> HTH, Ken
>
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>
--
Danny Gratzer
