flex/src/nfa.c

298  *   new = link_machines( first, last );
300  *     new    - a machine constructed by connecting first to last
301  *     first  - the machine whose successor is to be last
302  *     last   - the machine whose predecessor is to be first
304  * note: this routine concatenates the machine first with the machine
305  *  last to produce a machine new which will pattern-match first first
310 int     link_machines (int first, int last)
312 	if (first == NIL)
316 		return first;
319 		mkxtion (finalst[first], last);
320 		finalst[first] = finalst[last];
321 		lastst[first] = MAX (lastst[first], lastst[last]);
322 		firstst[first] = MIN (firstst[first], firstst[last]);
324 		return first;
333  * The "beginning" states are the epsilon closure of the first state
367  *   branch = mkbranch( first, second );
369  *     branch - a machine which matches either first's pattern or second's
370  *     first, second - machines whose patterns are to be or'ed (the | operator)
372  * Note that first and second are NEITHER destroyed by the operation.  Also,
377 int     mkbranch (int first, int second)
381 	if (first == NO_TRANSITION)
385 		return first;
389 	mkxtion (eps, first);
450  *   new = mkor( first, second );
452  *     new - a machine which matches either first's pattern or second's
453  *     first, second - machines whose patterns are to be or'ed (the | operator)
455  * note that first and second are both destroyed by the operation
460 int     mkor (int first, int second)
464 	if (first == NIL)
468 		return first;
471 		/* See comment in mkopt() about why we can't use the first
472 		 * state of "first" or "second" if they satisfy "FREE_EPSILON".
476 		first = link_machines (eps, first);
478 		mkxtion (first, second);
480 		if (SUPER_FREE_EPSILON (finalst[first]) &&
481 		    accptnum[finalst[first]] == NIL) {
482 			orend = finalst[first];
489 			mkxtion (finalst[first], orend);
495 			first = link_machines (first, eps);
496 			orend = finalst[first];
502 	finalst[first] = orend;
503 	return first;
637 		 * first time.