Data.Relational

Deprecated: This module will be replaced in a future release.

Tuples and relations.

Classes

class Tuple t where

Class for tuples.

Minimal complete definition

makeTuple, attributes

Associated Types

type Attribute t :: *

Type for attributes.

Methods

makeTuple :: [Attribute t] -> t

Make a tuple.

attributes :: t -> [Attribute t]

Retrieve attributes.

Instances

Tuple (Record a)

Associated Types

type Attribute (Record a) :: *

Methods

makeTuple :: [Attribute (Record a)] -> Record a

attributes :: Record a -> [Attribute (Record a)]

class Tuple t => Relation n t r | r -> t, r -> n where

Class for relations.

Minimal complete definition

names, empty, makeRelation, tuples, attributeMaybe

Methods

names :: r -> [n]

Names for tuples.

empty :: [n] -> r

An empty relation.

makeRelation :: [n] -> [t] -> r

Make a relation.

tuples :: r -> [t]

Retrieve tuples.

attributeMaybe :: r -> n -> t -> Maybe (Attribute t)

Lookup an attribute.

attribute :: r -> n -> t -> Attribute t

Lookup an attribute.

Instances

Tuple r => Relation String r (Table r)

Methods

names :: Table r -> [String]

empty :: [String] -> Table r

makeRelation :: [String] -> [r] -> Table r

tuples :: Table r -> [r]

attributeMaybe :: Table r -> String -> r -> Maybe (Attribute r)

attribute :: Table r -> String -> r -> Attribute r

Orphan instances

(Relation n t r, Stringy n) => WithHeader r t

Methods

fromHeaderLists :: ([String], [t]) -> r

toHeaderLists :: r -> ([String], [t])

((~) * (Attribute t) a, Tuple t) => Listable t a

Methods

fromList :: [a] -> t

toList :: t -> [a]