DEPRECATED: Use grafter.rdf.formats/filename->rdf-format instead.

Given a filename we attempt to return an appropriate RDFFormat
object based on the files extension.

Convert a grafter IStatement into a Sesame statement.

Create an RDF langauge string out of a value string and a given
language tag.  Language tags should be keywords representing the
country code, e.g.

(language "Bonsoir" :fr)

You can use this to declare an RDF typed literal value along with
its URI.  Note that there are implicit coercions already defined for
many core clojure/java datatypes, so for common datatypes you
shounld't need this.

A multimethod to convert an RDF literal into a corresponding
Clojure type.  This method can be extended to provide custom
conversions.

DEPRECATED: Use grafter.rdf.formats/mimetype->rdf-format instead.

Given a mimetype string we attempt to return an appropriate
RDFFormat object based on the files extension.

Coerces destination into an java.io.Writer using
clojure.java.io/writer and returns an RDFSerializer.

Use this to capture the intention to write to a location in a
specific RDF format, e.g.

(grafter.rdf/add (rdf-serializer "/tmp/foo.nt" :format :nt) quads)

Accepts also the following optional options:

- :append        If set to true it will append new values to the end of
                 the file destination (default: `false`).

- :format        If a String or a File are provided the format parameter
                 can be optional (in which case it will be infered from
                 the file extension).  This should be a sesame RDFFormat
                 object.

- :encoding      The character encoding to be used (default: UTF-8)

- :prefixes      A map of RDF prefix names to URI prefixes.

Convert a sesame Statement into a grafter Quad.