module ALife.Creatur.AgentNamer
(
AgentNamer(..),
SimpleAgentNamer,
mkSimpleAgentNamer
) where
import ALife.Creatur (AgentId)
import ALife.Creatur.Counter (PersistentCounter, current, increment,
mkPersistentCounter)
import ALife.Creatur.Util (stateMap)
import Control.Monad.State (StateT, get, gets)
class AgentNamer n where
genName ∷ StateT n IO AgentId
data SimpleAgentNamer = SimpleAgentNamer
{
prefix ∷ String,
counter ∷ PersistentCounter
}
mkSimpleAgentNamer ∷ String → FilePath → SimpleAgentNamer
mkSimpleAgentNamer s f = SimpleAgentNamer s $ mkPersistentCounter f
withCounter ∷ StateT PersistentCounter IO x → StateT SimpleAgentNamer IO x
withCounter runProgram = do
u ← get
stateMap (\c → u {counter=c}) counter runProgram
instance AgentNamer SimpleAgentNamer where
genName = do
p ← gets prefix
k ← withCounter (increment >> current)
return $ p ++ show k