I take it you want undeclared variables to be used in a lexical scope instead of global. I don't see what functionality you're adding except for making 'my' optional. Nice idea though. I'd probably want a something-scoped prama to select which behaviour undeclared variables go to though. I'd guess you could implement this for perl6 if you wanted it bad enough.

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