Replace strategy contingency calculation with generic extent_product

Author: tturocy

src/games/game.h

@@ -892,14 +892,6 @@ class GameRep : public std::enable_shared_from_this<GameRep> {
   }
   /// Remove the strategy from the game
   virtual void DeleteStrategy(const GameStrategy &p_strategy) { throw UndefinedException(); }
-  /// Returns the number of strategy contingencies in the game
-  int NumStrategyContingencies() const
-  {
-    BuildComputedValues();
-    return std::transform_reduce(
-        m_players.begin(), m_players.end(), 0, std::multiplies<>(),
-        [](const std::shared_ptr<GamePlayerRep> &p) { return p->m_strategies.size(); });
-  }
   /// Returns the total number of actions in the game
   virtual int BehavProfileLength() const = 0;
   //@}

src/games/gameobject.h

@@ -335,6 +335,16 @@ template <class T, auto OuterMemFn, auto InnerMemFn> class NestedElementCollecti
     return result;
   }
 
+  /// @brief Returns the Cartesian product of the sizes of the inner ranges
+  std::size_t extent_product() const
+  {
+    auto outer = (m_owner.get()->*OuterMemFn)();
+    return std::accumulate(outer.begin(), outer.end(), static_cast<std::size_t>(1),
+                           [](std::size_t acc, const auto &element) {
+                             return acc * (element.get()->*InnerMemFn)().size();
+                           });
+  }
+
   iterator begin() const { return {m_owner, false}; }
   iterator end() const { return {m_owner, true}; }
 };

src/gui/gameframe.cc

@@ -1111,14 +1111,15 @@ void GameFrame::OnViewStrategic(wxCommandEvent &p_event)
       return;
     }
 
-    const int ncont = m_doc->GetGame()->NumStrategyContingencies();
-    if (!m_nfgPanel && ncont >= 50000) {
-      if (wxMessageBox(
-              wxString::Format(wxT("This game has %d contingencies in strategic form.\n"), ncont) +
-                  wxT("Performance in browsing strategic form will be poor,\n") +
-                  wxT("and may render the program nonresponsive.\n") +
-                  wxT("Do you wish to continue?"),
-              _("Large strategic game warning"), wxOK | wxCANCEL | wxALIGN_CENTER, this) != wxOK) {
+    if (const size_t contingencies = m_doc->GetGame()->GetStrategies().extent_product();
+        !m_nfgPanel && contingencies >= 50000) {
+      if (wxMessageBox(wxString::Format(wxT("This game has %d contingencies in strategic form.\n"),
+                                        contingencies) +
+                           wxT("Performance in browsing strategic form will be poor,\n") +
+                           wxT("and may render the program nonresponsive.\n") +
+                           wxT("Do you wish to continue?"),
+                       _("Large strategic game warning"), wxOK | wxCANCEL | wxALIGN_CENTER,
+                       this) != wxOK) {
         return;
       }
     }
@@ -1242,15 +1243,16 @@ void GameFrame::OnToolsEquilibrium(wxCommandEvent &)
 
   if (dialog.ShowModal() == wxID_OK) {
     if (dialog.UseStrategic()) {
-      const int ncont = m_doc->GetGame()->NumStrategyContingencies();
-      if (ncont >= 50000) {
-        if (wxMessageBox(wxString::Format(
-                             wxT("This game has %d contingencies in strategic form.\n"), ncont) +
-                             wxT("Performance in solving strategic form will be poor,\n") +
-                             wxT("and may render the program nonresponsive.\n") +
-                             wxT("Do you wish to continue?"),
-                         _("Large strategic game warning"), wxOK | wxCANCEL | wxALIGN_CENTER,
-                         this) != wxOK) {
+      if (const int contingencies = m_doc->GetGame()->GetStrategies().extent_product();
+          contingencies >= 50000) {
+        if (wxMessageBox(
+                wxString::Format(wxT("This game has %d contingencies in strategic form.\n"),
+                                 contingencies) +
+                    wxT("Performance in solving strategic form will be poor,\n") +
+                    wxT("and may render the program nonresponsive.\n") +
+                    wxT("Do you wish to continue?"),
+                _("Large strategic game warning"), wxOK | wxCANCEL | wxALIGN_CENTER,
+                this) != wxOK) {
           return;
         }
       }