And of course I like my sig because it's both an example of how to use B and it also reads directly from memory in perl-space to find the address of the currently executing code-block. It's sort of like a map in a mall except that the arrow points to your current lexically scoped block. Nifty. Or I think so anyway.

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