refactor: define struct StackElt instead of a tuple

src/petri_net_sog.cpp

@@ -301,7 +301,7 @@ Paths PetriNetSOG::ObservablePaths(SOG &sog, map<int, int> trans_obs) const {
     firable_trans = FirableObservableTrans(complete_aggr);
 
     // TODO: why create a couple if c already contains the state aggregate?
-    st.emplace(AggrPair(c, complete_aggr), firable_trans);
+    st.emplace(c, firable_trans);
   }
 
   sog.set_initial_state(c);
@@ -347,7 +347,7 @@ Paths PetriNetSOG::ObservablePaths(SOG &sog, map<int, int> trans_obs) const {
       {
         auto *reached_aggr = new Aggregate;
         bdd complete_aggr =
-            AccessibleEpsilon(GetSuccessor(elt.aggr_pair.second, t));
+            AccessibleEpsilon(GetSuccessor(elt.aggregate->state, t));
         reached_aggr->state = complete_aggr;
         Aggregate *pos = sog.FindState(reached_aggr);
 
@@ -356,12 +356,12 @@ Paths PetriNetSOG::ObservablePaths(SOG &sog, map<int, int> trans_obs) const {
           firable_trans = FirableObservableTrans(complete_aggr);
 
           // add transitions
-          elt.aggr_pair.first->successors.insert(
-              elt.aggr_pair.first->successors.begin(), Edge(reached_aggr, t));
+          elt.aggregate->successors.insert(elt.aggregate->successors.begin(),
+                                           Edge(reached_aggr, t));
 
           // add the aggregate and its predecessors to the graph
           sog.AddState(reached_aggr);
-          sog.AddPredecessor(reached_aggr, Edge(elt.aggr_pair.first, t));
+          sog.AddPredecessor(reached_aggr, Edge(elt.aggregate, t));
 
           // if the aggregate has no firable transitions
           if (firable_trans.empty()) {
@@ -372,7 +372,7 @@ Paths PetriNetSOG::ObservablePaths(SOG &sog, map<int, int> trans_obs) const {
 
             current_trace.pop_back();
           } else {
-            st.emplace(AggrPair(reached_aggr, complete_aggr), firable_trans);
+            st.emplace(reached_aggr, firable_trans);
           }
         } else {  // aggregate already exists
           if (!old) {
@@ -382,9 +382,9 @@ Paths PetriNetSOG::ObservablePaths(SOG &sog, map<int, int> trans_obs) const {
 
           current_trace.pop_back();
           delete reached_aggr;
-          elt.aggr_pair.first->successors.insert(
-              elt.aggr_pair.first->successors.begin(), Edge(pos, t));
-          sog.AddPredecessor(pos, Edge(elt.aggr_pair.first, t));
+          elt.aggregate->successors.insert(elt.aggregate->successors.begin(),
+                                           Edge(pos, t));
+          sog.AddPredecessor(pos, Edge(elt.aggregate, t));
 
           old = true;
         }

src/petri_net_sog.hpp

@@ -11,14 +11,13 @@
 // type definitions
 typedef std::vector<int> Path;
 typedef std::set<Path> Paths;
-
 typedef std::pair<Aggregate*, bdd> AggrPair;
+
 struct StackElt {
-  AggrPair aggr_pair;  // pair of aggregate and the bdd
-  Set firable_trans;   // set of firable transitions
+  Aggregate* aggregate;  // pair of aggregate and the bdd
+  Set firable_trans;     // set of firable transitions
 
-  StackElt(AggrPair p, Set s)
-      : aggr_pair(std::move(p)), firable_trans(std::move(s)) {}
+  StackElt(Aggregate* p, Set s) : aggregate(p), firable_trans(std::move(s)) {}
 };
 typedef std::stack<StackElt> Stack;