Type Alias DereferenceFromNamedConflictMode

The possible decisions for a single named graph that a FROM NAMED source's own dereferenced data already exposes under its own name:

• error: refuse to load the source.
• preferNamed: rewrite this graph's quads into the FROM NAMED graph too, discarding the source's graph.
• keepSource: leave this graph exactly as-is, so the source ends up exposing it alongside the FROM NAMED graph.