+
+ if(result->is_viable())
+ return result;
+
+ delete result;
+ return 0;
+}
+
+bool AndCondition::is_viable() const
+{
+ for(vector<Condition *>::const_iterator i=conditions.begin(); i!=conditions.end(); ++i)
+ if(!(*i)->is_viable())
+ return false;
+ return !conditions.empty();