code: func (r *Lexer) Bytes() []byte {
  	if r.token.kind == tokenUndef && r.Ok() {
  		r.FetchToken()
  	}
  	if !r.Ok() || r.token.kind != tokenString {
  		r.errInvalidToken("string")
  		return nil
  	}
  	ret := make([]byte, base64.StdEncoding.DecodedLen(len(r.token.byteValue)))
  	n, err := base64.StdEncoding.Decode(ret, r.token.byteValue)
  	if err != nil {
  		r.fatalError = &LexerError{
  			Reason: err.Error(),
  		}
  		return nil
  	}
  
  	r.consume()
  	return ret[:n]
  }
docs: // Bytes reads a string literal and base64 decodes it into a byte slice.