arvo: only allow a single %whom
(~(put by van) way (mint $:u.bod way /sys/vane/[p]/hoon q))
==
::
- %whom ..poke(who `p.gub)
+ %whom ..poke(who ~|(%whom-once ?>(?=(~ who) `p.gub)))
%wyrd %- %+ wyrd kel.p.gub
^- (list (pair term @))
:* hoon/hoon-version
