Basically, what happens is the grep tests each potential dir returned by its 2nd arg (the do block) to see if it's a directory. If it is, the entry ends up in @dirs...

It took me ages to figure this out, so it's worthy of a repeat. :o)

(Yes, it took 4 reads of perldoc -f grep to finally parse correctly.)

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Me spell chucker work grate. Need grandma chicken.