anchor.diff:      | reflectedMember
       | arguments
       | elementSelector
  +    | ('--' | '++')
       ;
   
   memberInvocation
  
positive.code: 
  additiveExpression
      : multiplicativeExpression
        (('+' | '-') multiplicativeExpression)*
      ;
  
  multiplicativeExpression 
      : exponentiationExpression
        (('*' | '/' | '%') exponentiationExpression)*
      ;
  
  exponentiationExpression
      : postfixExpression ('**' postfixExpression)?
      ;
  
  postfixExpression
      : unaryExpression ('--' | '++')*
      ;
  
  unaryExpression 
  
negative.code: 
  //should '^' have a higher precedence?
  disjunctionExpression
      : conjunctionExpression 
        ('||' conjunctionExpression)?
      ;
  
  conjunctionExpression
      : logicalNegationExpression 
        ('&&' logicalNegationExpression)*
      ;
  
  logicalNegationExpression
  