Don't put any grams into the prize if they weren't requested.
?~ soy ~
:+ ~ ~
:- %circle
- :+ %+ turn
+ :+ ?. (~(has in wat.qer) %grams) ~
+ %+ turn
=- (~(so-first-grams so:ta nom.qer ~ -) ran.qer)
::TODO this can be done more efficiently.
?~ wer.qer u.soy
