anchor.diff:      ;
   
   variable_declaration
  -    : type=data_type  decl+=declarator (',' decl+=declarator)
  +    : type=data_type  decl+=declarator (',' decl+=declarator)*
       ;
   
   declarator
  
positive.code:     ;
  
  statement
      : method_call
      | assignment_expression
      | variable_declaration
      | if_statement
  
negative.code:     | continue_statement
      ;
  
  call_statement
      : method_call
      | access method_access
      ;
  
  iterative_statement
      : repeat_statement
      | foreach_statement
  