#!/usr/bin/perl -T

use strict; 
use warnings;
use v5.10;

use Scalar::Util;
use locale;
use POSIX qw(locale_h);
setlocale(LC_CTYPE, "de_DE");

sub filter_string {
  my $s = shift;

  warn("raw string '$s' is tainted") if Scalar::Util::tainted($s);
  $s =~ m:^(.+?) \([0-9]{4}(/[IVX]+)?\).*?$: or die "String '$s' doesn't match";
  $s = $1;
  warn("filtered string '$s' is tainted") if Scalar::Util::tainted($s);
  $s;
}

my @strings = ('ABC1 (1945/IXV)',
	       'ABC2 (1945)',
	       'ABC3 (1945)',
	       'ABC4 (1945) {DEF()}',
	       'ABC5 (1945) {D ()}',
	       'ABC6 (1945) {D(#)}',
	       'ABC7 (1945) {D (#)}',
	       'ABC8 (1945) {()}',
	       'ABC9 (1945) {D ()}',
	       'ABC10 (1945) ()',
	       'ABC11 (1945) {()',
	       'ABC12 (1945) { ()}',
	       'ABC13 (1945) { ()',
	       'ABC14 (1945) x(/',
	       'ABC15 (1945) ( ',
	       'ABC16 (1945) (',
	       'ABC17 (1945) { (',
	       'ABC18 (1945) { (#',
  );

foreach my $s (@strings) {
  say filter_string($s);
}