parse_mode
static enum eqn_tok eqn_next(struct eqn_node *, enum parse_mode);
eqn_next(struct eqn_node *ep, enum parse_mode mode)
while (parse_mode == TOKEN) {
parse_mode = WHITESPACE;
parse_mode = QUOTED_STRING;
while (parse_mode == QUOTED_STRING) {
parse_mode = TOKEN;
register enum parse_mode parse_mode;
parse_mode = WHITESPACE; /* flushing whitespace */
printf ("character `%c', mode %d\n", *line_ptr, parse_mode);
while (parse_mode == WHITESPACE) {
parse_mode = QUOTED_STRING;
parse_mode = TOKEN;