{- |

Module : $Header$

Copyright : (c) Francisc-Nicolae Bungiu

License : GPLv2 or higher, see LICENSE.txt

Maintainer : Christian.Maeder@dfki.de

Stability : provisional

Portability : portable

RDF constructs

References:

<http://www.informatik.uni-bremen.de/~till/papers/ontotrans.pdf>

-}

module RDF.AS where

import Common.Id

import RDF.Keywords

import Data.Char (intToDigit)

import Data.List

import Data.Maybe

import qualified Data.Map as Map

import qualified Data.Set as Set

data RDFGraph = Set.Set RDFTriple

data Signature = Sign [ResourceReference]

data Sentence = Sen (Subject Predicate Object)

data RDFTriple = Triple (Subject Object Predicate)

data Subject = URIref | BlankNode

data Predicate = URIref

data Object = URIref | Literal | BlankNode

data Node = URIref | Literal | BlankNode deriving (Show, Eq, Ord)

data Datatype = ValueSpace | LexicalSpace | Map.Map ValueSpace LexicalSpace

data TypedOrUntyped = Typed DatatypeURI | Untyped DatatypeURI

deriving (Show, Eq, Ord)

data Literal = Literal LexicalForm TypedOrUntyped

| Literal LexicalForm PlainLiteral (Maybe LanguageTag)

deriving (Show, Eq, Ord)