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https://issues.apache.org/jira/browse/TINKERPOP-1764?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16147330#comment-16147330
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ASF GitHub Bot commented on TINKERPOP-1764:
-------------------------------------------

GitHub user okram opened a pull request:

    https://github.com/apache/tinkerpop/pull/702

    TINKERPOP-1764: Generalize MatchStep to localize all barriers, not just 
reducing barriers.

    https://issues.apache.org/jira/browse/TINKERPOP-1764
    
    Prior to this moment, only reducing barrier steps in a `match()`-clause 
forced the clause to be computed locally (via a `flatMap()`-wrap). However, it 
has been deemed important to generalize this behavior to all barriers (e.g. 
`order()`, `limit()`, etc.) as identified by @doanduyhai (Gremlin power user). 
As such, the generalization has been done, but at the expense of a breaking 
change. However, realize that this breaking change would only be breaking 
behavior that is "random" (and most users should not be doing anyways -- but 
you never know).
    
    *PREVIOUSLY*
    
    ```
    gremlin> g.V().match(
    ......1>   
__.as('a').outE('created').order().by('weight',decr).limit(1).inV().as('b'),
    ......2>   __.as('b').has('lang','java')
    ......3> ).select('a','b').by('name')
    ==>[a:marko,b:lop]
    ```
    
    *CURRENTLY*
    
    ```
    gremlin> g.V().match(
    ......1>   
__.as('a').outE('created').order().by('weight',decr).limit(1).inV().as('b'),
    ......2>   __.as('b').has('lang','java')
    ......3> ).select('a','b').by('name')
    ==>[a:marko,b:lop]
    ==>[a:josh,b:ripple]
    ==>[a:peter,b:lop]
    ```
    
    VOTE +1

You can merge this pull request into a Git repository by running:

    $ git pull https://github.com/apache/tinkerpop TINKERPOP-1764

Alternatively you can review and apply these changes as the patch at:

    https://github.com/apache/tinkerpop/pull/702.patch

To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:

    This closes #702
    
----
commit 04b61d5943ecf12338ff15181ff01ba6fd2f143b
Author: Marko A. Rodriguez <[email protected]>
Date:   2017-08-30T14:33:34Z

    generalized match() to locally compute with all barriers, not just reducing 
barriers.

----


> Generalize MatchStep to localize all barriers, not just reducing barriers.
> --------------------------------------------------------------------------
>
>                 Key: TINKERPOP-1764
>                 URL: https://issues.apache.org/jira/browse/TINKERPOP-1764
>             Project: TinkerPop
>          Issue Type: Bug
>          Components: process
>    Affects Versions: 3.2.6
>            Reporter: Marko A. Rodriguez
>
> Given the semantics of order()/aggregate()/dedup(), this should work 
> currently (perhaps), but I will make it explicit in MatchStep and provide 
> test cases to ensure expected behavior. 



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