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https://issues.apache.org/jira/browse/TINKERPOP-1529?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15664774#comment-15664774
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ASF GitHub Bot commented on TINKERPOP-1529:
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Github user okram commented on the issue:
https://github.com/apache/tinkerpop/pull/485
Why add methods to `Traversal`? Why add a new `TraversalStrategy`? To solve
this problem in particular, why not just "walk right" and if you see a "lazy
side-effect" like `StoreStep`, then turn trigger a flag in
`LazyBarrierStrategy` to not apply barriers. You can then turn back on the flag
if you there are no more steps that introspect into the side-effect.
For example:
`g.V().out().out().store('a').out().out().cap('a').out().out()`
This would compile to:
`g.V().out().barrier().out().barrier().store('a').out().out().cap('a').barrier().out().barrier().out()`
> LazyBarrierStrategy is too agressive
> ------------------------------------
>
> Key: TINKERPOP-1529
> URL: https://issues.apache.org/jira/browse/TINKERPOP-1529
> Project: TinkerPop
> Issue Type: Bug
> Components: process
> Affects Versions: 3.2.3
> Reporter: Daniel Kuppitz
> Assignee: Daniel Kuppitz
>
> There are scenarios where {{LazyBarrierStrategy}} changes the semantics of a
> traversal:
> {noformat}
> gremlin> g = TinkerFactory.createModern().traversal()
> ==>graphtraversalsource[tinkergraph[vertices:6 edges:6], standard]
> gremlin> g.V().store("a").out().select("a")
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> {noformat}
> This is actually not the result of {{store()}}, this is {{aggregate()}}. The
> expected result for {{store()}} would be:
> {noformat}
> ==>[v[1]]
> ==>[v[1]]
> ==>[v[1]]
> ==>[v[1],v[2],v[3],v[4]]
> ==>[v[1],v[2],v[3],v[4]]
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> {noformat}
> Another issue, which should probably go into another ticket, is this:
> {noformat}
> gremlin>
> g.withoutStrategies(LazyBarrierStrategy).V().store("a").out().select("a")
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> {noformat}
> That's it, the console is hanging at this point. Looks like
> {{PathRetractionStrategy}} is the remaining troublemaker. With both
> strategies excluded, we get the expected result:
> {noformat}
> gremlin> g.withoutStrategies(LazyBarrierStrategy,
> PathRetractionStrategy).V().store("a").out().select("a")
> ==>[v[1]]
> ==>[v[1]]
> ==>[v[1]]
> ==>[v[1],v[2],v[3],v[4]]
> ==>[v[1],v[2],v[3],v[4]]
> ==>[v[1],v[2],v[3],v[4],v[5],v[6]]
> {noformat}
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