Swish.RDF.Parser.N3

This Module implements a Notation 3 parser, returning a new RDFGraph consisting of triples and namespace information parsed from the supplied N3 input string, or an error indication.

REFERENCES:

• "Notation3 (N3): A readable RDF syntax", W3C Team Submission 14 January 2008, http://www.w3.org/TeamSubmission/2008/SUBM-n3-20080114/
• Tim Berners-Lee's design issues series notes and description, http://www.w3.org/DesignIssues/Notation3.html
• Notation 3 Primer by Sean Palmer, http://www.w3.org/2000/10/swap/Primer.html

NOTES:

• The parser needs to be updated to the latest version ("W3C Team Submission 28 March 2011", http://www.w3.org/TeamSubmission/2011/SUBM-n3-20110328/)
• UTF-8 handling is not really tested.
• No performance testing has been applied.
• Not all N3 grammar elements are supported, including:
• @forSome (we read it in but ignore the arguments)
• @forAll (this causes a parse error)
• formulae are lightly tested
• string support is incomplete (e.g. unrecognized escape characters such as \q are probably handled incorrectly)

Documentation

type ParseResult = Either String RDFGraph

The result of a parse, which is either an error message or a graph.

parseN3

Arguments

:: Text

input in N3 format.

-> Maybe QName

optional base URI

-> ParseResult

Parse a string with an optional base URI.

See also parseN3fromString.

parseN3fromText

Arguments

:: Text

input in N3 format.

-> ParseResult

Parse a string as N3 (with no real base URI).

See parseN3 if you need to provide a base URI.

parseAnyfromText

Arguments

:: N3Parser a

parser to apply

-> Maybe QName

base URI of the input, or Nothing to use default base value

-> Text

input to be parsed

-> Either String a

Function to supply initial context and parse supplied term.

parseTextFromText :: String -> Text -> Either String String

Used in testing.

parseAltFromText :: String -> String -> Text -> Either String String

Used in testing.

parseNameFromText :: Text -> Either String String

Used in testing.

parseAbsURIrefFromText :: Text -> Either String URI

Used in testing.

parseLexURIrefFromText :: Text -> Either String URI

Used in testing.

parseURIref2FromText :: Text -> Either String ScopedName

Used in testing.

Exports for parsers that embed Notation3 in a bigger syntax

type N3Parser a = Parser N3State a

The N3 parser.

data N3State

N3 parser state

Constructors

N3State

Fields

• graphState :: RDFGraph
• thisNode :: RDFLabel
• prefixUris :: NamespaceMap
• syntaxUris :: SpecialMap
• nodeGen :: Word32
• keywordsList :: [Text]
• allowLocalNames :: Bool

type SpecialMap = Map String ScopedName

Type for special name lookup table

getPrefix :: N3Parser ()

Process the remainder of an @prefix line (after this has been processed). The prefix value and URI are added to the parser state.

n3symbol :: N3Parser ScopedName

Match a N3 symbol (an explicit URI or a QName) and convert it to a ScopedName.

quickVariable :: N3Parser RDFLabel

Match ?name.

lexUriRef :: N3Parser URI

An explicitly given URI followed by white space.

document :: N3Parser RDFGraph

Process a N3 document, returning a graph.

subgraph :: RDFLabel -> N3Parser RDFGraph

Process a sub graph and assign it to the given label.

newBlankNode :: N3Parser RDFLabel

Create a new blank node.