ProjectM36.Relation

Documentation

attributes :: Relation -> Attributes

attributeNames :: Relation -> Set AttributeName

attributeForName :: AttributeName -> Relation -> Either RelationalError Attribute

attributesForNames :: Set AttributeName -> Relation -> Attributes

atomTypeForName :: AttributeName -> Relation -> Either RelationalError AtomType

mkRelationFromList :: Attributes -> [[Atom]] -> Either RelationalError Relation

emptyRelationWithAttrs :: Attributes -> Relation

mkRelation :: Attributes -> RelationTupleSet -> Either RelationalError Relation

mkRelationDeferVerify :: Attributes -> RelationTupleSet -> Either RelationalError Relation

mkRelationFromTuples :: Attributes -> [RelationTuple] -> Either RelationalError Relation

relationTrue :: Relation

relationFalse :: Relation

singletonTuple :: Relation -> Maybe RelationTuple

union :: Relation -> Relation -> Either RelationalError Relation

project :: AttributeNames -> Relation -> Either RelationalError Relation

rename :: AttributeName -> AttributeName -> Relation -> Either RelationalError Relation

arity :: Relation -> Int

degree :: Relation -> Int

cardinality :: Relation -> RelationCardinality

group :: AttributeNames -> AttributeName -> Relation -> Either RelationalError Relation

restrictEq :: RelationTuple -> Relation -> Either RelationalError Relation

ungroup :: AttributeName -> Relation -> Either RelationalError Relation

tupleUngroup :: AttributeName -> Attributes -> RelationTuple -> Either RelationalError Relation

attributesForRelval :: AttributeName -> Relation -> Either RelationalError Attributes

type RestrictionFilter = RelationTuple -> Either RelationalError Bool

restrict :: RestrictionFilter -> Relation -> Either RelationalError Relation

join :: Relation -> Relation -> Either RelationalError Relation

difference :: Relation -> Relation -> Either RelationalError Relation

Difference takes two relations of the same type and returns a new relation which contains only tuples which appear in the first relation but not the second.

relMap :: (RelationTuple -> Either RelationalError RelationTuple) -> Relation -> Either RelationalError Relation

relMogrify :: (RelationTuple -> Either RelationalError RelationTuple) -> Attributes -> Relation -> Either RelationalError Relation

relFold :: (RelationTuple -> a -> a) -> a -> Relation -> a

toList :: Relation -> IO [RelationTuple]

Generate a randomly-ordered list of tuples from the relation.

imageRelationFor :: RelationTuple -> Relation -> Either RelationalError Relation

typesAsRelation :: TypeConstructorMapping -> Either RelationalError Relation

Return a Relation describing the types in the mapping.

relationVariablesAsRelation :: Map RelVarName Relation -> Either RelationalError Relation

Return a Relation describing the relation variables.

randomizeTupleOrder :: MonadRandom m => Relation -> m Relation

Randomly resort the tuples. This is useful for emphasizing that two relations are equal even when they are printed to the console in different orders.

oneTuple :: Relation -> Maybe RelationTuple