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-- 2001, 2002 Peter Thiemann
module Main where
import Prelude hiding (map, span, head, div)
import WASH.CGI.CGI
import qualified Persistent2 as P
counterStore :: CGI (P.T Int)
counterStore = P.init "Counter" 0
main =
run mainCGI
mainCGI =
forever counter
counter = do
counterHandle <- counterStore
counterValue <- P.get counterHandle
standardQuery "Counter" $ p $
do text "Current counter value "
text (show counterValue)
br empty
submit0 (count counterHandle (counterValue+1)) (fieldVALUE "Increment")
submit0 (count counterHandle (counterValue-1)) (fieldVALUE "Decrement")
count h n = do
r <- P.set h n
case r of
Just _ ->
return ()
Nothing ->
standardQuery "CounterMistake" $ p $
do text "Your attempt to set the counter to "
text (show n)
text " was not successful. "
text "Someone else was quicker :-)"
submit0 (return ()) (fieldVALUE "Continue")
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