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-- 2001-2005 Peter Thiemann
module Main where
import Char
import Prelude hiding (head, span, map)
import WASH.CGI.CGI hiding (div)
main =
run mainCGI
mainCGI =
calc "0" id
calc dstr f =
standardQuery "Calculator" $ table $
do dsp <- tr (td (textInputField (attr "value" dstr ## attr "name" "result")
## attr "colspan" "4"))
let button c = td (submit dsp (calcAction c f)
(attr "value" [c] ## attr "name" ('k': [c])))
tr (button '1' ## button '2' ## button '3' ## button '+')
tr (button '4' ## button '5' ## button '6' ## button '-')
tr (button '7' ## button '8' ## button '9' ## button '*')
tr (button 'C' ## button '0' ## button '=' ## button '/')
calcAction c f dsp
| isDigit c = calc (dstr ++ [c]) f
| c == 'C' = mainCGI
| c == '=' = calc (show (f (read dstr :: Integer))) id
| otherwise = calc "0" (optable c (read dstr :: Integer))
where dstr = value dsp
optable '+' = (+)
optable '-' = (-)
optable '*' = (*)
optable '/' = div
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