[3/7] tinkerpop git commit: added a really neat explain() to TraversalStrategy section of the docs which details how various strategies effect the compilation process. Built the-traversal.asciidoc locally and all is good. CTR.

[sp...@apache.org]

added a really neat explain() to TraversalStrategy section of the docs which details how various strategies effect the compilation process. Built the-traversal.asciidoc locally and all is good. CTR.


Project: http://git-wip-us.apache.org/repos/asf/tinkerpop/repo
Commit: http://git-wip-us.apache.org/repos/asf/tinkerpop/commit/e331164c
Tree: http://git-wip-us.apache.org/repos/asf/tinkerpop/tree/e331164c
Diff: http://git-wip-us.apache.org/repos/asf/tinkerpop/diff/e331164c

Branch: refs/heads/TINKERPOP-1467-master
Commit: e331164c0f0d0b3380a1075f48cd5c9dd698c04a
Parents: c0b6e79
Author: Marko A. Rodriguez <ok...@gmail.com>
Authored: Wed Sep 28 15:52:38 2016 -0600
Committer: Marko A. Rodriguez <ok...@gmail.com>
Committed: Wed Sep 28 15:52:38 2016 -0600

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 docs/src/reference/the-traversal.asciidoc | 40 ++++++++++++++++++++++----
 1 file changed, 34 insertions(+), 6 deletions(-)
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http://git-wip-us.apache.org/repos/asf/tinkerpop/blob/e331164c/docs/src/reference/the-traversal.asciidoc
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diff --git a/docs/src/reference/the-traversal.asciidoc b/docs/src/reference/the-traversal.asciidoc
index 4f7bff5..55963f4 100644
--- a/docs/src/reference/the-traversal.asciidoc
+++ b/docs/src/reference/the-traversal.asciidoc
@@ -2443,17 +2443,20 @@ public final class TinkerGraphStepStrategy extends AbstractTraversalStrategy<Tra
         if (TraversalHelper.onGraphComputer(traversal))
             return;
 
-        TraversalHelper.getStepsOfClass(GraphStep.class, traversal).forEach(originalGraphStep -> {
-            final TinkerGraphStep<?,?> tinkerGraphStep = new TinkerGraphStep<>(originalGraphStep);
-            TraversalHelper.replaceStep(originalGraphStep, (Step) tinkerGraphStep, traversal);
+        for (final GraphStep originalGraphStep : TraversalHelper.getStepsOfClass(GraphStep.class, traversal)) {
+            final TinkerGraphStep<?, ?> tinkerGraphStep = new TinkerGraphStep<>(originalGraphStep);
+            TraversalHelper.replaceStep(originalGraphStep, tinkerGraphStep, traversal);
             Step<?, ?> currentStep = tinkerGraphStep.getNextStep();
             while (currentStep instanceof HasContainerHolder) {
-                ((HasContainerHolder) currentStep).getHasContainers().forEach(tinkerGraphStep::addHasContainer);
-                currentStep.getLabels().forEach(tinkerGraphStep::addLabel);
+                for (final HasContainer hasContainer : ((HasContainerHolder) currentStep).getHasContainers()) {
+                    if (!GraphStep.processHasContainerIds(tinkerGraphStep, hasContainer))
+                        tinkerGraphStep.addHasContainer(hasContainer);
+                }
+                TraversalHelper.copyLabels(currentStep, tinkerGraphStep, false);
                 traversal.removeStep(currentStep);
                 currentStep = currentStep.getNextStep();
             }
-        });
+        }
     }
 
     public static TinkerGraphStepStrategy instance() {
@@ -2477,6 +2480,31 @@ t.iterate(); null
 t.toString()
 ----
 
+Finally, here is a complicated traversal that has various components that are optimized by the default TinkerPop strategies.
+
+[gremlin-groovy,modern]
+----
+g.V().hasLabel('person'). <1>
+        and(has('name','marko'),filter(has('age',gt(20)))). <2>
+  match(__.as('a').has('age',lt(32)), <3>
+        __.as('a').repeat(outE().inV()).times(2).as('b')). <4>
+    where('a',neq('b')). <5>
+    where(__.as('b').both().count().is(gt(1))). <6>
+  select('b'). <7>
+  groupCount().
+    by(out().count()). <8>
+  explain()
+----
+
+<1> `TinkerGraphStepStrategy` pulls in `has()`-step predicates for global, graph-centric index lookups.
+<2> `InlineFilterStrategy` de-nests filters to increase the likelihood of filter concatenation and aggregation.
+<3> `InlineFilterStrategy` pulls out named predicates from `match()`-step to more easily allow provider strategies to use indices.
+<4> `RepeatUnrollStrategy` will unroll loops and `IncidentToAdjacentStrategy` will turn `outE().inV()`-patterns into `out()`.
+<5> `MatchPredicateStrategy` will pull in `where()`-steps so that they can be subjected to `match()`-steps runtime query optimizer.
+<6> `RangeByIsCountStrategy` will limit the traversal to only the number of traversers required for the `count().is(x)`-check.
+<7> `PathRetractionStrategy` will remove paths from the traversers and increase the likelihood of bulking as path data is not required after `select('b')`.
+<8> `AdjacentToIncidentStrategy` will turn `out()` into `outE()` to increase data access locality.
+
 WARNING: The reason that `OptimizationStrategy` and `ProviderOptimizationStrategy` are two different categories is
 that optimization strategies should only rewrite the traversal using TinkerPop3 steps. This ensures that the
 optimizations executed at the end of the optimization strategy round are TinkerPop3 compliant. From there, provider