I would say this is a radix sort: 
my $pchr = "KQRBNP";
my $w1 = "QRKPNBNBQRK";

my %s;
$s{$_}++ for split //, $w1;
my $w2 = $pchr =~ s/(.)/$1 x $s{$1}/egr;

print "$w1 -> $w2\n"

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In reply to Re: Sort list by position of items in another list by salva
in thread Sort list by position of items in another list by gflohr

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