#!/usr/bin/perl
use Modern::Perl;
# 943829

my $str = "<Master ID='foobar\nblivitz' NameUI='12345'";
if ( $str =~ /<Master ID='(.*?)' NameUI='(.*?)'/sg ) {
    say "\$1: $1";
    say "\$2: $2";
}else{
    say "WTH?"
}

##</code><code>##

$1: foobar
blivitz
$2: 12345