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/^(?=.*a)(?=.*b)(?=.*c).*d/
   or die;

my %order;
@order{qw( a b c d )} =
...
   or die;

my @ordered = sort { $order{$a} <=> $order{$b} } keys %order;

my @order = map length, /^(?=(.*?)a)(?=(.*?)b)(?=(.*?)c)(.*?)d/
   or die;
...
my @ordered = ( qw( a b c d ) )[
   sort { $order[$a] <=> $order[$b] } 0..$#order
];

my @unordered = qw( a b c d );

...
my @ordered = @unordered[
   sort { $order[$a] <=> $order[$b] } 0..$#order
];