anchor.diff:      | BIN_INTEGER
       ;
   
  -testlist_comp
  -    : (test | star_expr) (comp_for | (COMMA (test | star_expr))* COMMA?)
  -    ;
  -
   lambdef
       : LAMBDA varargslist? COLON test
       ;
  
positive.code:     | (test | star_expr) (comp_for | (COMMA (test | star_expr))* COMMA?)
      ;
  
  classdef
      : CLASS name (OPEN_PAREN arglist? CLOSE_PAREN)? COLON suite
      ;
  
  arglist
  
negative.code:     | STAR
      ;
  
  named_parameter
      : name (COLON test)?
      ;
  