I'm thinking NFA since that'll be easier for me to get my head around. I prefer not to have to think about multi-d things accumulating in memory - and then there are local pockets of extra dimensions. Blech. No way.

__SIG__
use B;
printf "You are here %08x\n", unpack "L!", unpack "P4", pack
  "L!", B::svref_2object(sub{})->OUTSIDE;
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