anchor.diff:  * Null predicate
   * Not-null predicate
   
  -|3
  +|9
   |https://raw.githack.com/openCypher/openCypher/master/tools/grammar-production-links/grammarLink.html?p=UnaryAddOrSubtractExpression[Arithmetic additive inverse]
   |
   
   * Unary negative
   * Unary positive
   
  -|4
  +|8
   |https://raw.githack.com/openCypher/openCypher/master/tools/grammar-production-links/grammarLink.html?p=PowerOfExpression[Exponentiation] (left-hand and right-hand operand)
   |
   
   * Exponentiation
   
  -|5
  +|7
   |https://raw.githack.com/openCypher/openCypher/master/tools/grammar-production-links/grammarLink.html?p=MultiplyDivideModuloExpression[Arithmetic multiplicative operations] (left-hand and right-hand operand)
   |
   
  
positive.code: 
  |===
  
  
  == What others do
  
  
negative.code: * Less
  * Less or Equal
  
  |4
  |https://raw.githack.com/openCypher/openCypher/master/tools/grammar-production-links/grammarLink.html?p=NotExpression[Boolean negation] (left-hand and right-hand operand)
  |
  
  * Negation
  
  |3
  |https://raw.githack.com/openCypher/openCypher/master/tools/grammar-production-links/grammarLink.html?p=AndExpression[Boolean conjunction] (left-hand and right-hand operand)
  |
  
  * Conjunction
  
  |2
  |https://raw.githack.com/openCypher/openCypher/master/tools/grammar-production-links/grammarLink.html?p=XorExpression[Boolean exclusive disjunction] (left-hand and right-hand operand)
  |
  
  * Exclusive disjunction
  
  |1
  |https://raw.githack.com/openCypher/openCypher/master/tools/grammar-production-links/grammarLink.html?p=OrExpression[Boolean inclusive disjunction] (left-hand and right-hand operand)
  |
  
  