#ifndef __LEXAN
#define __LEXAN

#include <iostream>
#include "token.h"

class lexan
{ protected:
    istream & in;
    token oldtoken;
    bool useoldtoken;

  public:
    lexan(): in(cin), oldtoken(terror, "", 0), useoldtoken(false) { }
    lexan(istream & i): in(i), oldtoken(terror, "", 0), useoldtoken(false) { }
    void unnext(token t);
    token next(); };

#endif