You could treat the hash as an array and modify the key

Sure you could, but why?

Re-construct the entire hash to modify just one key? That's feasible, but only for small hashes, since you are duplicating all keys and values of the hash into a temporary list. Pretty much overhead.

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