Yes. Next question.
Next question: why?
Seriously, what's wrong with a much easier approach like this?

Somebody could mess with the package global $FOO_HAS_BEEN_CALLED and blow things up, and call_me_only_once() gets called twice. Of course, call_me_once() disposing of itself properly after being called would make damn sure it isn't a second time :-)

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re^2: Is modifying the symbol table to redefine subroutines evil? by shmem
in thread Is modifying the symbol table to redefine subroutines evil? by tlm

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