Github user afs commented on a diff in the pull request:
https://github.com/apache/jena/pull/394#discussion_r182114929
--- Diff:
jena-arq/src/main/java/org/apache/jena/sparql/algebra/OpWalker.java ---
@@ -139,6 +139,7 @@ protected void visitN(OpN op) {
@Override
protected void visitExt(OpExt op) {
before(op) ;
+ super.visitExt(op);
--- End diff --
There are probably both cases. Its an extension point so it is hard to be
categorical. Only the effective is walkable unless the OpExt is comprised of
known Ops in which case it does not need to be an OpExt.
Let's leave it as per the PR - we might have to return to it but without a
concrete alternative usage, it feels like slipping towards guessing.
---
