#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my $string = '\\w';
$string =~ s/(\\)+/\\/g;
print "PRINT: $string\n";
print Dumper "DUMPER: ".$string;

Ergebnis:
PRINT: \w
$VAR1 = 'DUMPER: \\w';