when i "runhaskell BigSession.hs" i don't get the recv error message of "yesod devel" but sometimes a Nothing from "lookupSession": If you clear cookies, go to /start/3000 you get Nothing. If you clear cookies, go to /start/2500 you get 2500. If you go to /start/3000 afterwards you still get 2500. So "clearSession" seems not to not always work c…

BigSession.hs

{-# LANGUAGE TypeFamilies, QuasiQuotes, MultiParamTypeClasses,
             TemplateHaskell, OverloadedStrings #-}
import Yesod
import Data.Text (Text,unpack,pack)

data BigSession = BigSession

mkYesod "BigSession" [parseRoutes|
/start/#Int StartR GET
/error ErrorR GET
|]

instance Yesod BigSession

getStartR :: Int -> Handler RepHtml
getStartR size = do
  clearSession
  setSession "error" $ pack $ take size $ repeat '1'
  redirect ErrorR

getErrorR :: Handler RepHtml
getErrorR = do
  x <- lookupSession "error"
  let x' = case x of
             Nothing -> "Nothing"
             Just y  -> show $ length $ unpack y
  defaultLayout $ [whamlet|#{x'}<br>
<a href=@{StartR 2500}>start 2500
<a href=@{StartR 3000}>start 3000
|]

main :: IO ()
main = warpDebug 3000 BigSession