emit
Emit traversers before or after a repeat() step.
Synopsis
emit( [ 'predicate' | 'traversal' ])| Syntax conventions | Description |
|---|---|
| Lowercase and uppercase | Literal keyword. Includes (). |
Italics |
Variable value. Replace with a user-defined value. |
[] |
Optional. Square brackets ( [] ) surround
optional command arguments. Do not type the square brackets. |
{} |
Group. Braces ( {} ) identify a group to choose
from. Do not type the braces. |
| |
Or. A vertical bar ( | ) separates alternative
elements. Type any one of the elements. Do not type the vertical
bar. |
... |
Repeatable. An ellipsis ( ... ) indicates that
you can repeat the syntax element as often as required. |
Description
The emit() step is a step
modulator, a helper step for another traversal step. Its main use is to emit either
incoming traversers before a repeat() step, or emit
outgoing traversers after a repeat() step. The emission sends a copy of the
current objects to the next step in the query. A predicate or traversal can be used in an emit() step to cause the
emission only if the predicate or traversal is true.
Examples
g.V(1).emit().repeat(out()).times(2).path()
==>[v[1]]
==>[v[1],v[3]]
==>[v[1],v[2]]
==>[v[1],v[4]]
==>[v[1],v[4],v[5]]
==>[v[1],v[4],v[3]]
gremlin> g.V(1).repeat(out()).times(2).emit().path()
==>[v[1],v[3]]
==>[v[1],v[2]]
==>[v[1],v[4]]
==>[v[1],v[4],v[5]]
==>[v[1],v[4],v[3]]