LATERAL: Unexpectedly unbound variable.

[Aklakan]

Version

5.3.0-SNAPSHOT

What happened?

I am not sure whether this is according to SEP7 or a bug in Jena:

I am trying to inject a value using lateral into a BIND in a subquery. The following works:

SELECT * {
  BIND('x' AS ?xIn)
  LATERAL {
    { SELECT * { BIND(?xIn AS ?xOut) } }
  }
}

The result is:

?xIn	?xOut
x	x

However, if in the lateral block there is a Join, then it breaks:

SELECT * {
  BIND('x' AS ?xIn)
  LATERAL {
    BIND("foo" AS ?foo)
    { SELECT * { BIND(?xIn AS ?xOut) } }
  }
}

In the result, ?xOut is (for me) unexpectedly unbound.

?xIn	?foo	?xOut
x	foo

I think this is a bug in Jena (but perhaps I am misunderstanding something about the scoping rules).

Relevant output and stacktrace

No response

Are you interested in making a pull request?

Maybe