anchor.diff:  ----
   
   === Interaction with existing features
  -This replaces the pre-existing `HAS(...)` function.
  +
  +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.
  +This is very similar to what SQL does with its `EXISTS` functionality.
   
  -This is also very similar in syntax to what SPARQL does with its EXISTS functionality; the rules regarding variables are identical, and the inner query also takes a subquery as input.
  +This is also very similar in syntax to what SPARQL does with its `EXISTS` functionality; the rules regarding variables are identical, and the inner query also takes a subquery as input.
   
   == Benefits to this proposal
   
  
positive.code: 
  == Background
  
  In a way, Cypher already has existential subqueries - pattern predicates allow checking for the existence of subgraphs.
  This form is helpful, but not exhaustive in the types of subqueries that users want to be able to express.
  
  == Proposal
  
  To make this feature more powerful, add a new function named `exists`, and a keyword named the same, which allows for two different predicates:
  
   * Property existence checking
   * Subquery existence checking
  
  === Syntax
  
  
negative.code: ----
  MATCH (actor:Actor)
  WHERE EXISTS {
    (other:Actor)-[:ACTED_IN]->(movie)<-[:ACTED_IN]-(actor)
    WHERE other.name = actor.name
  }
  RETURN actor
  ----
  