anchor.diff:  RETURN actor
   ----
   
  -=== Interaction with existing features
  -
  -The `EXISTS {}` subquery clause renders obsolete the current pattern predicate syntax.
  -This allows the pattern predicates to be deprecated and/or removed in favour of `EXISTS {}`.
  -
   == What others do
   
   This is very similar to what SQL does with its `EXISTS` functionality.
  
positive.code: RETURN team
  ----
  
  == Caveats to this proposal
  
  Subqueries are powerful constructs. As such they can be difficult to understand, and difficult for a query planner to get right.
  
negative.code: 
  This proposal also allows for powerful subqueries, for example using aggregation inside the `EXISTS {}` query.
  
  Find all teams that have at least two members who have worked on successful projects.
  [source, cypher]
  ----
  MATCH (team:Team)
  