Database.PostgreSQL.Store.RowParser

Row Parser

data RowParser a

Row parser

Instances

Monad RowParser

Methods

(>>=) :: RowParser a -> (a -> RowParser b) -> RowParser b

(>>) :: RowParser a -> RowParser b -> RowParser b

return :: a -> RowParser a

fail :: String -> RowParser a

Functor RowParser

Methods

fmap :: (a -> b) -> RowParser a -> RowParser b

(<$) :: a -> RowParser b -> RowParser a

Applicative RowParser

Methods

pure :: a -> RowParser a

(<*>) :: RowParser (a -> b) -> RowParser a -> RowParser b

(*>) :: RowParser a -> RowParser b -> RowParser b

(<*) :: RowParser a -> RowParser b -> RowParser a

MonadError RowError RowParser

Methods

throwError :: RowError -> RowParser a

catchError :: RowParser a -> (RowError -> RowParser a) -> RowParser a

data RowErrorLocation

Location of an error

Constructors

RowErrorLocation Column Row

Instances

Eq RowErrorLocation

Methods

(==) :: RowErrorLocation -> RowErrorLocation -> Bool

(/=) :: RowErrorLocation -> RowErrorLocation -> Bool

Ord RowErrorLocation

Methods

compare :: RowErrorLocation -> RowErrorLocation -> Ordering

(<) :: RowErrorLocation -> RowErrorLocation -> Bool

(<=) :: RowErrorLocation -> RowErrorLocation -> Bool

(>) :: RowErrorLocation -> RowErrorLocation -> Bool

(>=) :: RowErrorLocation -> RowErrorLocation -> Bool

max :: RowErrorLocation -> RowErrorLocation -> RowErrorLocation

min :: RowErrorLocation -> RowErrorLocation -> RowErrorLocation

Show RowErrorLocation

Methods

showsPrec :: Int -> RowErrorLocation -> ShowS

show :: RowErrorLocation -> String

showList :: [RowErrorLocation] -> ShowS

data RowErrorDetail

Errors that occur during row parsing

Constructors

TooFewColumns

Underlying RowParser wants more columns than are currently present.

ColumnRejected TypedValue

A column value could not be parsed.

ContentsRejected (Maybe ByteString)

The contents of a column could not be parsed.

Instances

Eq RowErrorDetail

Methods

(==) :: RowErrorDetail -> RowErrorDetail -> Bool

(/=) :: RowErrorDetail -> RowErrorDetail -> Bool

Ord RowErrorDetail

Methods

compare :: RowErrorDetail -> RowErrorDetail -> Ordering

(<) :: RowErrorDetail -> RowErrorDetail -> Bool

(<=) :: RowErrorDetail -> RowErrorDetail -> Bool

(>) :: RowErrorDetail -> RowErrorDetail -> Bool

(>=) :: RowErrorDetail -> RowErrorDetail -> Bool

max :: RowErrorDetail -> RowErrorDetail -> RowErrorDetail

min :: RowErrorDetail -> RowErrorDetail -> RowErrorDetail

Show RowErrorDetail

Methods

showsPrec :: Int -> RowErrorDetail -> ShowS

show :: RowErrorDetail -> String

showList :: [RowErrorDetail] -> ShowS

data RowError

An error that occured when parsing a row.

Constructors

RowError RowErrorLocation RowErrorDetail

Instances

Eq RowError

Methods

(==) :: RowError -> RowError -> Bool

(/=) :: RowError -> RowError -> Bool

Ord RowError

Methods

compare :: RowError -> RowError -> Ordering

(<) :: RowError -> RowError -> Bool

(<=) :: RowError -> RowError -> Bool

(>) :: RowError -> RowError -> Bool

(>=) :: RowError -> RowError -> Bool

max :: RowError -> RowError -> RowError

min :: RowError -> RowError -> RowError

Show RowError

Methods

showsPrec :: Int -> RowError -> ShowS

show :: RowError -> String

showList :: [RowError] -> ShowS

MonadError RowError RowParser

Methods

throwError :: RowError -> RowParser a

catchError :: RowParser a -> (RowError -> RowParser a) -> RowParser a

rowNumber :: RowParser Row

Retrieve the current row number.

columnNumber :: RowParser Column

Retrieve the current column number.

columnsLeft :: RowParser Column

Retrieve the number of columns left.

fetchColumn :: RowParser TypedValue

Fetch the type Oid and value of the current cell. Also advances the cell cursor to the next column.

peekColumn :: RowParser TypedValue

Fetch the TypedValue associated with the current cell without advancing the cursor.

parseColumn :: (TypedValue -> Maybe a) -> RowParser a

Fetch a column and parse it. Returning Nothing from the provided parser function will cause a ColumnRejected to be raised. Advances the cell cursor to the next column.

peekContents :: RowParser (Maybe ByteString)

Fetch the cell's contents without moving the cell cursor.

fetchContents :: RowParser (Maybe ByteString)

Like peekContents but moves the cell cursor to the next column.

parseContents :: (ByteString -> Maybe a) -> RowParser a

Parse the contents of a column (only if present). Returning Nothing from the provided parser function will raise a ContentsRejected. When the cell is NULL, a ContentsRejected is raised aswell.

skipColumn :: RowParser ()

Point cursor to the next column.

Result Parser

parseResult :: Result -> RowParser a -> ExceptT RowError IO [a]

Parse the result.