When running with 0.5.2 I was able to do this traversal to add an edge between to vertices

gremlin> g.addV()

==>v[8200]

gremlin> g.addV()

==>v[4336]
gremlin> g.V(8200).addE('my_edge_label').to(g.V(4336))

But when doing it through 0.6.0 I get this now:

gremlin> g.V(8200).addE('my_edge_label').to(g.V(4336))

The child traversal of [GraphStep(vertex,[4336])] was not spawned anonymously - use the __ class rather than a TraversalSource to construct the child traversal

Type ':help' or ':h' for help.

Display stack trace? [yN]y

java.lang.IllegalStateException: The child traversal of [GraphStep(vertex,[4336])] was not spawned anonymously - use the __ class rather than a TraversalSource to construct the child traversal

at org.apache.tinkerpop.gremlin.process.traversal.Bytecode.convertArgument(Bytecode.java:302)

at org.apache.tinkerpop.gremlin.process.traversal.Bytecode.flattenArguments(Bytecode.java:287)

at org.apache.tinkerpop.gremlin.process.traversal.Bytecode.addStep(Bytecode.java:94)

at org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversal.to(GraphTraversal.java:1145)

at org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversal$to$4.call(Unknown Source)

at Script148.run(Script148.groovy:1)

at org.apache.tinkerpop.gremlin.groovy.jsr223.GremlinGroovyScriptEngine.eval(GremlinGroovyScriptEngine.java:676)

at org.apache.tinkerpop.gremlin.groovy.jsr223.GremlinGroovyScriptEngine.eval(GremlinGroovyScriptEngine.java:378)

at javax.script.AbstractScriptEngine.eval(AbstractScriptEngine.java:233)

at org.apache.tinkerpop.gremlin.groovy.engine.GremlinExecutor.lambda$eval$0(GremlinExecutor.java:272)

at java.util.concurrent.FutureTask.run(FutureTask.java:266)

at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)

at java.util.concurrent.FutureTask.run(FutureTask.java:266)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)

at java.lang.Thread.run(Thread.java:748)

gremlin>

After fiddling with it though I noticed I was able to do this:

gremlin> g.V(4336).as('test').V(8200).addE('my_edge_label').to('test')

==>e[2dd-6bs-xzp-3cg][8200-my_edge_label->4336]

However just doing the vertex id is not permitted, which makes sense given it's just an integer with no context.

gremlin> g.V(8200).addE('my_edge_label').to(4336)

No signature of method: org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.DefaultGraphTraversal.to() is applicable for argument types: (Integer) values: [4336]

Possible solutions: is(java.lang.Object), take(int), tap(groovy.lang.Closure), by(groovy.lang.Closure), drop(int), any()

I've been looking through the 0.6.0 milestone and found this issue, but that seemed more about a documentation change in 0.6.0 than a code change. Environment wise I'm just running these in a gremlin session within a docker-compose environment with Cassandra and Elasticsearch as backends.

Just wondering if the change here is intentional? Seemed weird that it was suggesting to the use "__" class too.