Tons of bugfixes (lots with closures). Added safe_recursive_delete to mem which helps easily and safely delete recursive data structures, and used it in regex. It still has a leak, but it's a lot better than before.

stdlib/regex.krak

@@ -63,7 +63,7 @@ obj regex(Object) {
 
     fun destruct():void {
         regexString.destruct()
-        //mem::safe_recursive_delete(begin, fun(it: regexState*): set::set<regexState*> { return set::set(it); } )
+        mem::safe_recursive_delete(begin, fun(it: regexState*): set::set<regexState*> { return set::from_vector(it->next_states); } )
     }
 
     fun operator=(other: regex):void {