g.V(..).in(..).<some contraints that do not change it from a vertex).
fold().project("visits", "form").
by(__.unfold().values("...").dedup().count()).
by(__.unfold().
repeat( __.in()).
emit(__.<etc>))
g.V(..).in(..).<some contraints that do not change it from a vertex).
fold().project("visits", "form").
by(__.unfold().values("...").dedup().count()).
by(__.unfold().
repeat( __.in()).
emit(__.<etc>))