Repository: tinkerpop Updated Branches: refs/heads/TINKERPOP-1708 [created] 6579b017e
added A Note on Scopes to the-traversal docs. Project: http://git-wip-us.apache.org/repos/asf/tinkerpop/repo Commit: http://git-wip-us.apache.org/repos/asf/tinkerpop/commit/6579b017 Tree: http://git-wip-us.apache.org/repos/asf/tinkerpop/tree/6579b017 Diff: http://git-wip-us.apache.org/repos/asf/tinkerpop/diff/6579b017 Branch: refs/heads/TINKERPOP-1708 Commit: 6579b017ee0d377d7428c1c182d8009a4153d859 Parents: c8cc0e5 Author: Marko A. Rodriguez <okramma...@gmail.com> Authored: Fri Jun 30 12:33:07 2017 -0600 Committer: Marko A. Rodriguez <okramma...@gmail.com> Committed: Fri Jun 30 12:33:07 2017 -0600 ---------------------------------------------------------------------- docs/src/reference/the-traversal.asciidoc | 43 ++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/tinkerpop/blob/6579b017/docs/src/reference/the-traversal.asciidoc ---------------------------------------------------------------------- diff --git a/docs/src/reference/the-traversal.asciidoc b/docs/src/reference/the-traversal.asciidoc index f39fe11..8af40df 100644 --- a/docs/src/reference/the-traversal.asciidoc +++ b/docs/src/reference/the-traversal.asciidoc @@ -2574,6 +2574,49 @@ possible at the current, local vertex. What it can't compute without referencing into a barrier collection. When there are no more traversers at the local vertex, the barriered traversers are the messages that are propagated to remote vertices for further processing. +[[a-note-on-scopes]] +A Note on Scopes +---------------- + +The `Scope` enum has two constants: `Scope.local` and `Scope.global`. Scope determines whether the particular step +being scoped is with respects to the current object (`local`) at that step or to the entire stream of objects up to that +step ('global'). + +[gremlin-groovy,modern] +---- +g.V().has('name','marko').out('knows').count() <1> +g.V().has('name','marko').out('knows').fold().count() <2> +g.V().has('name','marko').out('knows').fold().count(local) <3> +g.V().has('name','marko').out('knows').fold().count(global) <4> +---- + +<1> Marko knows 2 people. +<2> A list of Marko's friends is created and thus, one object is counted (the single list). +<3> A list of Marko's fiends is created and a `local`-count yields the number of objects in that list. +<4> `count(global)` is the same as `count()` as the default behavior for most scoped steps is `global`. + +The steps that support scoping are: + +* <<count-step,`count()`>>: count the local collection or global stream. +* <<dedup-step, `dedup()`>>: dedup the local collection of global stream. +* <<max-step, `max()`>>: get the max value in the local collection or global stream. +* <<mean-step, `mean()`>>: get the mean value in the local collection or global stream. +* <<min-step, `min()`>>: get the min value in the local collection or global stream. +* <<order-step,`order()`>>: order the objects in the local collection or global stream. +* <<range-step, `range()`>>: clip the local collection or global stream. +* <<sample-step, `sample()`>>: sample objects from the local collection or global stream. +* <<tail-step, `tail()`>>: get the tail of the objects in the local collection or global stream. + +A few more examples of the use of `Scope` are provided below: + +[gremlin-groovy,modern] +---- +g.V().both().group().by(label).select('software').dedup(local) +g.V().groupCount().by(label).select(values).min(local) +g.V().groupCount().by(label).order(local).by(values,decr) +g.V().fold().sample(local,2) +---- + [[a-note-on-lambdas]] A Note On Lambdas -----------------
