On Sat, Aug 17, 2013 at 11:59:24PM +0200, Hartmut Pfarr wrote:
> {-# LANGUAGE OverloadedStrings #-}
>
> import Database.PostgreSQL.Simple
> import Database.PostgreSQL.Simple.FromRow
>
> hello :: (FromRow a) => IO [a]
> hello = do
> conn <- connect defaultConnectInfo
> query_ conn "select 2 + 2"
Either
main = print =<< (hello :: IO [Int])
or give hello a monomorphic type signature, such as
hello :: IO [Int]
Tom
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