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https://issues.apache.org/jira/browse/TINKERPOP-2430?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17206099#comment-17206099
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ASF GitHub Bot commented on TINKERPOP-2430:
-------------------------------------------
spmallette commented on a change in pull request #1336:
URL: https://github.com/apache/tinkerpop/pull/1336#discussion_r498755636
##########
File path: docs/src/recipes/looping.asciidoc
##########
@@ -0,0 +1,88 @@
+////
+Licensed to the Apache Software Foundation (ASF) under one or more
+contributor license agreements. See the NOTICE file distributed with
+this work for additional information regarding copyright ownership.
+The ASF licenses this file to You under the Apache License, Version 2.0
+(the "License"); you may not use this file except in compliance with
+the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+////
+[[looping]]
+== Looping
+One common use case when working with Gremlin is to perform complex looping
statements using the `repeat()` step. While many of the common patterns for
looping within traversals are discussed in the documentation there are several
more complex patterns that include additional steps which are also commonly
used. This section attempts to demonstrate how to use some of these more
complex measurements.
+
+image:tree-lca.png[width=230,float=right] The following examples will use this
graph depicted here:
+
+[gremlin-groovy]
+----
+g.addV().property(id, 'A').as('a').
+ addV().property(id, 'B').as('b').
+ addV().property(id, 'C').as('c').
+ addV().property(id, 'D').as('d').
+ addV().property(id, 'E').as('e').
+ addV().property(id, 'F').as('f').
+ addV().property(id, 'G').as('g').
+ addE('hasParent').from('a').to('b').
+ addE('hasParent').from('b').to('c').
+ addE('hasParent').from('d').to('c').
+ addE('hasParent').from('c').to('e').
+ addE('hasParent').from('e').to('f').
+ addE('hasParent').from('g').to('f').iterate()
+----
+
+=== Conditional Looping with Max Depth
+
+One common situation encountered when writing `repeat()` loop is the need to
exit the loop when either a specific condition is met or a maximum depth is
reached. Given that graph above the following traversal demonstrates how to
accomplish this type of complex exit condition. In this example the traversal
will start at vertex A and loop through all outgoing edges until it reaches
vertex C or it until it has completed 3 loops.
+
+[gremlin-groovy,existing]
+----
+g.V('A').
+ repeat(out().simplePath()).
+ until(hasId('C').or().loops().is(3))
+----
+
+In the above case the traversal processes the `out().simplePath()` step once
to move from vertex A to vertex B, a second time to move from vertex B to
vertex C, and then exits the traversal because it satisfies the `hasId('C')`
condition since it's reached vertex C. If we however change that exit
condition to be vertex G, we will see that this traversal now will continue to
process thorough vertex X and will exit based on reaching the maximum number of
loops (3).
+
+[gremlin-groovy,existing]
+----
+g.V('A').
+ repeat(out().simplePath()).
+ until(hasId('G').or().loops().is(3))
+----
+
+The key portion of the above traversal is the `until()` step. This step is
capable of accepting a `Traversal` object will keep the `repeat()` loop
traversing until the evaluated output of the traversal is true, which causes
the traverser to exit the `repeat()` loop. Using the methodology allows
complex logical conditions to be used as the exit criteria.
Review comment:
accepting a `Traversal` object will keep the `repeat()`" - perhaps
"object which will"?
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> Looping Recipies
> ----------------
>
> Key: TINKERPOP-2430
> URL: https://issues.apache.org/jira/browse/TINKERPOP-2430
> Project: TinkerPop
> Issue Type: Improvement
> Components: documentation
> Reporter: Dave Bechberger
> Priority: Minor
>
> Create documentation recipes for common looping patterns including:
> Conditional Looping with Max Depth
> Emitting the Loop Depth
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