I guess there is a lot of powerful stuff going on there that I don't follow.

- for ( 1 .. $num_refs ) {
+ for ( $num_refs .. 1 ) {
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That's not what happens when I try it. For example,

perl -e "$n=5; for($n..1) { print }"
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does not print the reverse of

perl -e "$n=5; for(1..$n) { print }"
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