Either do as saouq sez and just don't create a mis-feature or... jump right in and do the beastly thing yourself (you do no one favors by enabling bad behaviour). If I were to actually do this you could also consider keeping track of how many tags have been opened and be sure to close them before ending your user-accessible section.

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