Hi Monks

I'm trying to solve a dereference problem. Can I someway get substitution to accept progressive matching. Only way I could use the pos() command is below, but that is not a very good way (as far as speed is concerned and I don't like it 'couse it's doing things twice). So any better way to do this? 
#!/usr/bin/perl

use warnings;
use strict;
# use re "debug";

my %CSV = ('n' => 'n',
           't' => 't',
           'f' => 'f',
           '\\' => '\\',
          );


$_ = '\\\\\\\\\\';
print "$_\n";
my $pos = 0;
while (m/\\(.)/g) { $pos=pos($_);}
s/\\(.)/exists($CSV{$1}) ? "\\$1" : "\\\\$1"/ge;
s/^(.{$pos})\\$/$1\\\\/;

print "result:\n$_\n";

[download]

The first subst works fine until it hits the last character. If that is a single backstroke, then it needs to be dereferenced, but if not then not.

In reply to Regex to dereference by Hena

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