Drat. This won't work because he didn't:

use Quantum::Superpositions;
use strict;

my   @word;

push @word, qr/\bfee\b/;
push @word, qr/\bfi\b/;
push @word, qr/\bfo\b/;
push @word, qr/\bfum\b/;

my $str  = 'tweedle fee hi fi mo fo drunk on some fum';

if ($str =~ all(@word)) {
    warn "$str contains all of @word";
}
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