module ProjectM36.AttributeNames where
import ProjectM36.Base
import qualified Data.Set as S
--AttributeNames is a data structure which can represent inverted projection attributes and attribute names derived from relational expressions

empty :: AttributeNamesBase a
empty :: AttributeNamesBase a
empty = Set AttributeName -> AttributeNamesBase a
forall a. Set AttributeName -> AttributeNamesBase a
AttributeNames Set AttributeName
forall a. Set a
S.empty

all :: AttributeNamesBase a
all :: AttributeNamesBase a
all = Set AttributeName -> AttributeNamesBase a
forall a. Set AttributeName -> AttributeNamesBase a
InvertedAttributeNames Set AttributeName
forall a. Set a
S.empty