text: // scan.h
  // Copyright (c) Randall Bohn 2019
  // BSD 2 Clause License
  
  // use char * because cc65 can't do plaid\H\H\H\H\Hinteger arrays
  void scan(char *s);
  void accept(char token, char *text, int len);
  
  #define BLANK 'B'
  #define NUMBER 'N'
  #define OPERATOR 'O'
  #define OTHER '?'
  #define EOL 'Z'
  
  // operators
  #define O_NONE 0
  #define O_ADD 1
  #define O_SUB 2
  #define O_MUL 3
  #define O_DIV 4
  #define O_MOD 5
  
  