Database.PostgreSQL.Store.Result

Contents

Description

Synopsis

Result processor

Error that occured during result processing

Constructors

TooFewColumnsError Column	Occurs when you're trying to access a column that does not exist.
UnpackError Row Column Oid Format	The value at a given row and column could not be unpacked.

Instances

Eq ResultError Source #
Methods (==) :: ResultError -> ResultError -> Bool # (/=) :: ResultError -> ResultError -> Bool #
Show ResultError Source #
Methods showsPrec :: Int -> ResultError -> ShowS # show :: ResultError -> String # showList :: [ResultError] -> ShowS #
MonadError ResultError ResultProcessor Source #
Methods throwError :: ResultError -> ResultProcessor a # catchError :: ResultProcessor a -> (ResultError -> ResultProcessor a) -> ResultProcessor a #

Result processor

Instances

Monad ResultProcessor Source #
Methods (>>=) :: ResultProcessor a -> (a -> ResultProcessor b) -> ResultProcessor b # (>>) :: ResultProcessor a -> ResultProcessor b -> ResultProcessor b # return :: a -> ResultProcessor a # fail :: String -> ResultProcessor a #
Functor ResultProcessor Source #
Methods fmap :: (a -> b) -> ResultProcessor a -> ResultProcessor b # (<$) :: a -> ResultProcessor b -> ResultProcessor a #
Applicative ResultProcessor Source #
Methods pure :: a -> ResultProcessor a # (<>) :: ResultProcessor (a -> b) -> ResultProcessor a -> ResultProcessor b # (>) :: ResultProcessor a -> ResultProcessor b -> ResultProcessor b # (<*) :: ResultProcessor a -> ResultProcessor b -> ResultProcessor a #
MonadIO ResultProcessor Source #
Methods liftIO :: IO a -> ResultProcessor a #
MonadError ResultError ResultProcessor Source #
Methods throwError :: ResultError -> ResultProcessor a # catchError :: ResultProcessor a -> (ResultError -> ResultProcessor a) -> ResultProcessor a #

Process the entire result set.

Process one row of the result set.

Move cursor to the next column.

Unpack the current column and move the cursor to the next column.