Notice that he never says exactly what goes into @features. You need to put something in which can equal 2 or 3 things at the same time. Interesting, this succeeds:

if (any(any("tall", "rich")) eq all("tall", "rich")) {
    print "yes\n";
}
[download]

But this doesn't:

if (any(any("tall", "rich")) eq any(all("ugly"), all("tall", "rich")))
+ {
    print "yes\n";
}
[download]

Methinks there's a bug lurking in there, but then, you were warned