Merge pull request #914 from tgbugs/keep-prefixes

make round tripping of prefixes configurable

1 files changed, 10 insertions, 0 deletions

diff --git a/rdflib/plugins/serializers/turtle.py b/rdflib/plugins/serializers/turtle.py
index 3a1e5a61..1c58ba1b 100644
--- a/rdflib/plugins/serializers/turtle.py
+++ b/rdflib/plugins/serializers/turtle.py
@@ -43,6 +43,7 @@ class RecursiveSerializer(Serializer):
     predicateOrder = [RDF.type, RDFS.label]
     maxDepth = 10
     indentString = u"  "
+    roundtrip_prefixes = tuple()
 
     def __init__(self, store):
 
@@ -110,6 +111,15 @@ class RecursiveSerializer(Serializer):
         self._subjects = {}
         self._topLevels = {}
 
+        if self.roundtrip_prefixes:
+            if hasattr(self.roundtrip_prefixes, '__iter__'):
+                for prefix, ns in self.store.namespaces():
+                    if prefix in self.roundtrip_prefixes:
+                        self.addNamespace(prefix, ns)
+            else:
+                for prefix, ns in self.store.namespaces():
+                    self.addNamespace(prefix, ns)
+
     def buildPredicateHash(self, subject):
         """
         Build a hash key by predicate to a list of objects for the given