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definition:
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getDBInfo :: (Read a, Show a) => KeyPred a -> Key -> Query (Maybe a)
getDBInfo keyPred key = Query $
do rows <- selectRows keyPred "*" $ "where _rowid_ = " ++ show key
readHeadIfExists rows
where
readHeadIfExists [] = return Nothing
readHeadIfExists (x:_) = return $!! Just (readInfo x)
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demand:
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no demanded arguments
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deterministic:
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deterministic operation
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documentation:
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--- Queries the information stored under the given key. Yields
--- <code>Nothing</code> if the given key is not present.
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failfree:
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<FAILING>
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indeterministic:
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referentially transparent operation
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infix:
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no fixity defined
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iotype:
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{(_,_,_,_) |-> _}
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name:
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getDBInfo
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precedence:
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no precedence defined
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result-values:
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_
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signature:
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(Prelude.Read a, Prelude.Show a) => (Prelude.Int -> a -> Dynamic) -> Prelude.Int
-> Query (Prelude.Maybe a)
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solution-complete:
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operation might suspend on free variables
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terminating:
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possibly non-terminating
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totally-defined:
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possibly non-reducible on same data term
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