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+Stream Processing
+=================
+
+.. default-domain:: c
+.. highlight:: c
+
+The above examples show how a document can be either written to a file or loaded into a model,
+simply by changing the sink that the data is written to.
+There are also sinks that filter or transform the data before passing it on to another sink,
+which can be used to build more advanced pipelines with several processing stages.
+
+Canonical Literals
+------------------
+
+A `canon` is a stream processor that converts literals with supported XSD datatypes into canonical form.
+For example, this will rewrite an xsd:decimal literal like ".10" as "0.1".
+A canon is created with :func:`serd_canon_new`,
+which needs to be passed the "target" sink that the transformed statements should be written to,
+for example:
+
+.. literalinclude:: overview_code.c
+ :start-after: begin canon-new
+ :end-before: end canon-new
+ :dedent: 2
+
+The last argument is a bitwise ``OR`` of :enum:`SerdCanonFlag` flags.
+For example, :enumerator:`SERD_CANON_LAX` will tolerate and pass through invalid literals,
+which can be useful for cleaning up questionabe data as much as possible without losing any information.
+
+Filtering Statements
+--------------------
+
+A `filter` is a stream processor that filters statements based on a pattern.
+It can be configured in either inclusive or exclusive mode,
+which passes through only statements that match or don't match the pattern,
+respectively.
+A filter is created with :func:`serd_filter_new`,
+which takes a target, pattern, and inclusive flag.
+For example, all statements with predicate ``rdf:type`` could be filtered out when loading a model:
+
+.. literalinclude:: overview_code.c
+ :start-after: begin filter-new
+ :end-before: end filter-new
+ :dedent: 2
+
+If ``false`` is passed for the last parameter instead,
+then the filter operates in exclusive mode and will instead insert only statements with predicate ``rdf:type``.