salvia-0.0.4: src/Network/Salvia/Handlers/Counter.hs

module Network.Salvia.Handlers.Counter (hCounter) where

import Control.Monad.State
import Control.Concurrent.STM

import Network.Salvia.Httpd

hCounter :: TVar Int -> Handler ()
hCounter c = lift $ atomically
  $ readTVar c >>= writeTVar c . (+1)