I am trying to use zero-width negative lookahead assertions to add an AND NOT logical clause to my pattern. I wish to match /aaa/ and /aaa\/aaa/ but not /aaa/aaa/ which is to say a span delimited by unescaped slashes. What I have so far matches too much:

#!/usr/bin/perl

use strict;
use warnings;

while (<DATA>) {

    # print $+{pattern},qq(\n) if (

    # for now, show the whole line
    print if (
        m,
        ^
        (?!\x23)
        (?:.*?)
        (?<pattern>
        m?
        (?<delimiter>[/])
        (?:(?:\\?+.)*?)*?
        \g{delimiter}
        )
        ,x
        );
}


__DATA__

#!/usr/bin/perl
foo
bar
foo/bar
/src/bin/oops/otehnoes
if(/ok .*$/) {
    print "not OK\n";
}
# skip a comment
if(m/a good match/( {
    print "not ok\n";
}

# do not /print/ this line either
$string =~ s/[a-f]//g; # but print this line
( $string ) = ( $string =~ /(show this)/));
/but show\/this, too/
my $butdontprintthis = "/var/cache/dictionaries-common";

[download]

However, I have not found a successful way to match /aaa/ while at the same time rejecting /aaa/aaa/

What should I append towards the end of the pattern to ensure that /aaa/aaa/aaa/ and other similar strings are not accepted by the pattern yet /aaa/ alone would be? I have tried many scores of permutations of what to tack on, but no sucess yet. The script above produces the following result: 

/src/bin/oops/otehnoes
if(/ok .*$/) {
if(m/a good match/( {
$string =~ s/[a-f]//g; # but print this line
( $string ) = ( $string =~ /(show this)/));
/but show\/this, too/
my $dontprint this = "/var/cache/dictionaries-common";

[download]

But it should produce the following instead: 

if(/ok .*$/) {
if(m/a good match/( {
$string =~ s/[a-f]//g; # but print this line
( $string ) = ( $string =~ /(show this)/));
/but show\/this, too/

[download]

In reply to Regex AND NOT with zero-width negative lookahead assertion by mldvx4

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