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https://issues.apache.org/jira/browse/TINKERPOP-967?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16519611#comment-16519611
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ASF GitHub Bot commented on TINKERPOP-967:
------------------------------------------
Github user spmallette commented on the issue:
https://github.com/apache/tinkerpop/pull/876
Some more notes from Marko (i haven't had a chance to let them sink in
myself, just pasting them here):
```text
times(a,2) == loops(a,eq(2))
```
the idea being, you might want to check on the loop count of an outer loop
within an inner loop and vice versa. Basically, you are trying to solve:
```text
for(i=0;i<10) { for(j=0;j<10) if(i == x) …. } ….
```
the point being, you want to be able to check for `i` and `j` counters not
just at the loop check point but anywhere in the respective body.
And note that naming `repeat()`s is not the same as naming the
`repeat()`-step. It isn’t a step label……… though, some thinking on that might
be worth it. In essence `repeat(‘a’,…) != repeat(…).as(‘a’)`
the ‘a’ in the first is for the loop stack, not for the step label….but
again, perhaps there is a reason to unite the two concepts. Though if done so,
a new syntax would be introduced which would add an “irregularity” to Gremlin
> Support nested-repeat() structures
> ----------------------------------
>
> Key: TINKERPOP-967
> URL: https://issues.apache.org/jira/browse/TINKERPOP-967
> Project: TinkerPop
> Issue Type: Improvement
> Components: process
> Affects Versions: 3.1.0-incubating
> Reporter: Marko A. Rodriguez
> Assignee: Marko A. Rodriguez
> Priority: Major
>
> All the internal plumbing is staged for this to happen, we just haven't gone
> all the way. In short, a {{NESTED_LOOP}} traverser has an internal
> {{loopStack}} where {{repeat(repeat())}} will have a {{loopStack}} of two.
> The {{it.loops()}} checks of the internal repeat will always check the top of
> the stack and when its done repeating will delete its counter off the top of
> the stack.
> [~dkuppitz]'s work on {{LoopStep}} will be backwards compatible. In
> {{RepeatStep}} we will support:
> {code}
> repeat('a',out('knows').repeat('b',out('parent')))
> {code}
> and thus, things like {{loops('a')}} as well as {{times('a',2)}}. Note that
> naming the loop stack will be a super rare case as most people will just
> assume standard nested looping semantics with a push/pop stack.
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