小编Mic*_*ine的帖子

我的代码抛出一个空列表错误.当我跑:

makeAgent :: Agent -> [Agent] -> Agent
makeAgent (Agent func n _) agents = (Agent func (n++(show $ length $ sameNames n agents)) empty) --appends number to name to differentiate agents
    where sameNames n agents = filter (findName n) agents
          findName n1 (Agent _ n2 _) = (slice 0 3 n1) == (slice 0 3 n2) --ignore the suffix
          empty = head $ getEmpty (positions agents) (fst $ getGrid agents) --getGrid returns a tuple, but currently assume to be …