Use regexes with char classes: 

#!/usr/bin/perl
use warnings;
use strict;

my $allowed = "pure";
my $re = quotemeta $allowed;

my $str = "p u+r-e";
$str =~ s/[^$re]//g;
print $str, "\n";

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Perl 6 in German -- Difficult Sudoku

In reply to Re: Scurbbing a string by moritz
in thread Scrubbing a string by princepawn

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