Add example of improved option() capability. #173
Description
Release 3.4.3 added the ability for option steps used with a choose step to include traversals so constructs like the one below are now possible.
g.V().hasLabel('airport').
groupCount().
by(__.choose(__.values('elev')).
option(gt(5000),__.constant('high')).
option(gt(3000),__.constant('medium')).
option(Pick.none,__.constant('low')))
Also show to do it before would have taken something like
res = ( g.V().hasLabel('airport').
groupCount().
by(__.choose(__.values('elev').is_(gt(5000)),
__.constant('high'),
__.choose(__.values('elev').is_(gt(3000)),
__.constant('medium'),
__.constant('low')))).
order(Scope.local).by(Column.values).
next() )
As part of this also document the Pick enum.
org.apache.tinkerpop.gremlin.process.traversal.step.TraversalOptionParent.Pick
Maybe also show something like this as the old option usage
gremlin> g.V().hasLabel('airport').
......1> has('region','US-TX').fold().
......2> choose(count(local)).
......3> option(1,constant('one')).
......4> option(0,constant('none')).
......5> option(none,constant('neither one or zero'))
==>neither one or zero
gremlin> g.V().hasLabel('airport').
......1> has('code','AUS').fold().
......2> choose(count(local)).
......3> option(1,constant('one')).
......4> option(0,constant('none')).
......5> option(none,constant('neither one or zero'))
==>one
gremlin> g.V().hasLabel('airport').
......1> has('code','XYZ').fold().
......2> choose(count(local)).
......3> option(1,constant('one')).
......4> option(0,constant('none')).
......5> option(none,constant('neither one or zero'))
==>none
As part of this update the Pick enum needs to be added to the list of enum tables