anchor.diff:  grammar JakoParser;
   
   options {
  -//    backtrack=true;
  +    backtrack=true;
       memoize=true;
   //    k=2;
   }
  
positive.code: 	|	'~='
  	;
  
  logical_or_expression
  	:	logical_and_expression ( '||' logical_and_expression )*
  	;
  
  logical_and_expression
  	:	inclusive_or_expression ( '&&' inclusive_or_expression )*
  	;
  
  inclusive_or_expression
  	:	exclusive_or_expression ( '|' exclusive_or_expression )*
  	;
  
  exclusive_or_expression
  	:	and_expression ( '^' and_expression )*
  	;
  
  and_expression
  	:	equality_expression ( '&' equality_expression )*
  	;
  
  equality_expression
  	:	relational_expression ( ( '==' | '!=' ) relational_expression )*
  	;
  
  relational_expression
  	:	additive_expression ( ( '<' | '>' | '<=' | '>=' ) additive_expression )*
  	;
  
  //
  
negative.code: 	;
  	
  side_effect_statement
  	:	assignment_statement
  	|	expression
  	;
  
  assignment_statement
  	:	primary_expression assignment_operator expression
  	;
  
  assignment_operator
  