Redland RDF library bindings. See the original API for in-depth descriptions.

Library organization

• Raw bindings are provided by Redland.LowLevel. Normally they should not be used directly.
• Refined versions (using Haskell types) of those are provided by Redland.MidLevel. One should still be careful with the allocated resources while using those, for instance by using withNew. A rule of thumb is that whenever you see an Initializer, it's a good idea to wrap it into withNew.
• Utility functions and types are provided by Redland.Util. Those don't strictly correspond to functions of the original API.

Usage example

import Redland

input :: String
input = "<?xml version=\"1.0\"?>\
\<rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"\
\     xmlns:dc=\"http://purl.org/dc/elements/1.1/\">\
\  <rdf:Description rdf:about=\"http://www.dajobe.org/\">\
\    <dc:title>Dave Beckett's Home Page</dc:title>\
\    <dc:creator>Dave Beckett</dc:creator>\
\    <dc:description>The generic home page of Dave Beckett.</dc:description>\
\  </rdf:Description>\
\</rdf:RDF>\
\"

main :: IO ()
main =
  withWSMU "memory" [] "example" "" "http://example.librdf.org/" $
  \world storage model uri -> do
    -- parse and insert
    guessingParseStringIntoModel world model uri input
    -- query
    withQuery world model "sparql"
      "SELECT ?foo ?bar ?baz WHERE { ?foo ?bar ?baz }" (Just uri) $
      mapM_ print
    -- search statements
    withStatements world model (Triple Nothing Nothing Nothing) $
      mapM_ print

It prints the following:

[("foo",ResourceNode "http://www.dajobe.org/"),("bar",ResourceNode "http://purl.org/dc/elements/1.1/title"),("baz",LiteralNode "Dave Beckett's Home Page" Nothing)]
[("foo",ResourceNode "http://www.dajobe.org/"),("bar",ResourceNode "http://purl.org/dc/elements/1.1/creator"),("baz",LiteralNode "Dave Beckett" Nothing)]
[("foo",ResourceNode "http://www.dajobe.org/"),("bar",ResourceNode "http://purl.org/dc/elements/1.1/description"),("baz",LiteralNode "The generic home page of Dave Beckett." Nothing)]
Triple {subject = Just (ResourceNode "http://www.dajobe.org/"), predicate = Just (ResourceNode "http://purl.org/dc/elements/1.1/title"), object = Just (LiteralNode "Dave Beckett's Home Page" Nothing)}
Triple {subject = Just (ResourceNode "http://www.dajobe.org/"), predicate = Just (ResourceNode "http://purl.org/dc/elements/1.1/creator"), object = Just (LiteralNode "Dave Beckett" Nothing)}
Triple {subject = Just (ResourceNode "http://www.dajobe.org/"), predicate = Just (ResourceNode "http://purl.org/dc/elements/1.1/description"), object = Just (LiteralNode "The generic home page of Dave Beckett." Nothing)}