As for old functions, I'd really like to have a better way than "errsafe" for determining whether or not a variable is bound. But yeah, I agree this should work for not-yet-defined functions.
Edit: Okay, using bound, I updated redef (and thus defm) to not die if the function isn't already defined. See the following Anarki commits: http://git.nex-3.com/arc-wiki.git?a=commit;h=b8a2edb218634f3..., http://git.nex-3.com/arc-wiki.git?a=commit;h=d1fa9fd5d1f3eb1..., and http://git.nex-3.com/arc-wiki.git?a=commit;h=68f1a03eb4f07e5....
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