EntityStopWatchingWorldState

local function EntityWatchWorldState(self, var, fn)
    if self.worldstatewatching == nil then
        self.worldstatewatching = {}
    end

    local watcherfns = self.worldstatewatching[var]
    if watcherfns == nil then
        watcherfns = {}
        self.worldstatewatching[var] = watcherfns
    end

    table.insert(watcherfns, var)
end

May be "fn" ??

 table.insert(watcherfns, fn) ----> fn looks much better