Hello,

Here is what I am trying to do.

if ( m|/user/(?!prot/)| )

[download]
The problem is I cannot use negative lookahead to do it.

To do this, I have tried the following variations with no success.

#!/usr/local/bin/perl5.6.0 -w
use strict;

while ( <DATA> )
{
    chomp;

    #if ( m|/user/(?!prot/)| )      # Works
    #if ( m|/user/[^p]?[^r]?[^o]?[^t]?[^/]?| )
    #if ( m|/user/([^p]*?[^r]*?[^o]*?[^t]*?[^/]*?)?| )
    #if ( m|/user/[^p]+?[^r]+?[^o]+?[^t]+?[^/]+?| )
    #if ( m|/user/([^p]*[^r]*[^o]*[^t]*[^/]*)?| )
    {
        print qq{Disallow!! [$_]\n};
    }
    else
    {
        print qq{Allowed. [$_]\n};
    }
}

__DATA__
/user/prot/
/user/protrusions/
/user/a/
/user/backups

[download]
The only one that I want to print "Allowed", (not to match) is the first one "/user/prot/".

OT: Why cant I use negative lookahead?

Actually because I am trying to make a regex for an Apache LocationMatch section,
to disable some settings for all directories inside a users site, except for one,
'/user/prot'.
The regex engine in Apache though does not have lookaround assertion ability :(.

<LocationMatch  /user/(?!prot/) >
   <Limit GET>
         order allow,deny
         deny from all
    </Limit>
    AllowOverride None
</LocationMatch>

[download]
Any help is much appreciated.

Wonko

In reply to Negative Lookahead using negated character classes? by Wonko the sane

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