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import Database.HaskellDB
import TestConnect
import Control.Exception
import Dp037.Test_tb1
printRecord r = putStrLn $ show (r!c11) ++ " " ++ show (r!c12)
printRecords db = do
rs <- query db (table test_tb1)
mapM_ printRecord rs
testTrans db = do
insert db test_tb1 (c11 << constant 2 # c12 << constJust (-67))
fail "oops, that didn't work out"
handleErr io = catchJust userErrors io
(\e -> putStrLn $ "caught nasty exception: " ++ e)
test db = do
putStrLn "before transaction:"
handleErr $ printRecords db
handleErr $ transaction db (testTrans db)
putStrLn "after transaction:"
handleErr $ printRecords db
main = argConnect test
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