Github user jeremy-coulon commented on a diff in the pull request:
https://github.com/apache/jena/pull/394#discussion_r181407237
--- 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 --
Visiting the real OpExt is not useful for me but I can't say for other
people.---
