For any word: 
my $set='bat';
my $regexp;
for (my $i=1;$i<=length($set);$i++){
 my $x=join '|', map {"\\$_"} 1..$i;
 $regexp.="([$set])(?!$x)";
}
if (/^$regexp/){
  # do something
}

[download]
Terrible... :-)

In reply to Re: Re: Re: regular xpression stuff by Lucky
in thread regular xpression stuff by Anonymous Monk

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