anchor.diff:  
   binary_expression
     : binary_operator prefix_expression
  -  | assignment_operator try_operator? prefix_expression
  +// as far as I can tell, assignment is not a valid operator as it has no return type
  +// it is more properly a statement; commenting this next line out and moving to assignment_statement:
  +// | assignment_operator try_operator? prefix_expression
     | conditional_operator try_operator? prefix_expression
     | type_casting_operator
     ;
  
positive.code: 
  statements : statement+ ;
  
  // GRAMMAR OF A LOOP STATEMENT
  
  loop_statement : for_statement
  
negative.code: 
  statement
   : expression ';'?
   | assignment_statement ';'?
   | declaration ';'?
   | loop_statement ';'?
   | branch_statement ';'?
  