Last round of simplification of Signal/Slot classes

- merged all the common stuff from 0,1,2,3 argument versions into one common base class
- removed ReturnType template parameter as it was instantiated with "void" everywhere and the
  current ignores the return value of the callbacks anyway

4 files changed, 72 insertions, 108 deletions

diff --git a/src/FbTk/MenuTheme.hh b/src/FbTk/MenuTheme.hh
index b575860..d39b5df 100644
--- a/src/FbTk/MenuTheme.hh
+++ b/src/FbTk/MenuTheme.hh
@@ -130,7 +130,7 @@ public:
             m_hl_selected_pixmap->pixmap().dontFree();
     }
 
-    virtual Signal<void> &reconfigSig() { return Theme::reconfigSig(); }
+    virtual Signal<> &reconfigSig() { return Theme::reconfigSig(); }
 
     virtual MenuTheme &operator *() { return *this; }
     virtual const MenuTheme &operator *() const { return *this; }
diff --git a/src/FbTk/Signal.hh b/src/FbTk/Signal.hh
index 432bb3f..a7b91ba 100644
--- a/src/FbTk/Signal.hh
+++ b/src/FbTk/Signal.hh
@@ -22,7 +22,6 @@
 #ifndef FBTK_SIGNAL_HH
 #define FBTK_SIGNAL_HH
 
-#include "RefCount.hh"
 #include "Slot.hh"
 #include <algorithm>
 #include <list>
@@ -35,7 +34,7 @@ namespace FbTk {
 namespace SigImpl {
 
 /**
- * Parent class for all \c Signal[0...*] classes.
+ * Parent class for all \c Signal template classes.
  * It handles the disconnect and holds all the slots. The connect must be
  * handled by the child class so it can do the type checking.
  */
@@ -121,93 +120,66 @@ private:
     unsigned m_emitting;
 };
 
-struct EmptyArg {};
-
-} // namespace SigImpl
-
-
-/// Specialization for three arguments.
-template <typename ReturnType,
-          typename Arg1 = SigImpl::EmptyArg, typename Arg2 = SigImpl::EmptyArg, typename Arg3 = SigImpl::EmptyArg >
-class Signal: public SigImpl::SignalHolder {
+template <typename Arg1, typename Arg2, typename Arg3>
+class SignalTemplate: public SignalHolder {
 public:
-    void emit(Arg1 arg1, Arg2 arg2, Arg3 arg3) {
+    template<typename Functor>
+    SlotID connect(const Functor& functor) {
+        return SignalHolder::connect(SlotPtr( new Slot<Arg1, Arg2, Arg3, Functor>(functor) ));
+    }
+
+protected:
+    void emit_(Arg1 arg1, Arg2 arg2, Arg3 arg3) {
         begin_emitting();
         for ( Iterator it = begin(); it != end(); ++it ) {
             if(*it)
-                static_cast<SigImpl::SlotBase3<ReturnType, Arg1, Arg2, Arg3> &>(**it)(arg1, arg2, arg3);
+                static_cast<SigImpl::SlotTemplate<Arg1, Arg2, Arg3> &>(**it)(arg1, arg2, arg3);
         }
         end_emitting();
     }
+};
 
-    template<typename Functor>
-    SlotID connect(const Functor& functor) {
-        return SignalHolder::connect(SlotPtr(
-                        new SigImpl::Slot3<ReturnType, Arg1, Arg2, Arg3, Functor>(functor)
-                    ));
-    }
+} // namespace SigImpl
+
+
+/// Base template for three arguments.
+template <typename Arg1 = SigImpl::EmptyArg, typename Arg2 = SigImpl::EmptyArg, typename Arg3 = SigImpl::EmptyArg >
+class Signal: public SigImpl::SignalTemplate<Arg1, Arg2, Arg3> {
+public:
+    void emit(Arg1 arg1, Arg2 arg2, Arg3 arg3)
+    { SigImpl::SignalTemplate<Arg1, Arg2, Arg3>::emit_(arg1, arg2, arg3); }
 };
 
 /// Specialization for two arguments.
-template <typename ReturnType, typename Arg1, typename Arg2>
-class Signal<ReturnType, Arg1, Arg2, SigImpl::EmptyArg>: public SigImpl::SignalHolder {
+template <typename Arg1, typename Arg2>
+class Signal<Arg1, Arg2, SigImpl::EmptyArg>:
+        public SigImpl::SignalTemplate<Arg1, Arg2, SigImpl::EmptyArg> {
 public:
     void emit(Arg1 arg1, Arg2 arg2) {
-        begin_emitting();
-        for ( Iterator it = begin(); it != end(); ++it ) {
-            if(*it)
-                static_cast<SigImpl::SlotBase2<ReturnType, Arg1, Arg2> &>(**it)(arg1, arg2);
-        }
-        end_emitting();
-    }
-
-    template<typename Functor>
-    SlotID connect(const Functor& functor) {
-        return SignalHolder::connect(SlotPtr(
-                        new SigImpl::Slot2<ReturnType, Arg1, Arg2, Functor>(functor)
-                    ));
+        SigImpl::SignalTemplate<Arg1, Arg2, SigImpl::EmptyArg>::
+            emit_(arg1, arg2, SigImpl::EmptyArg());
     }
 };
 
 /// Specialization for one argument.
-template <typename ReturnType, typename Arg1>
-class Signal<ReturnType, Arg1, SigImpl::EmptyArg, SigImpl::EmptyArg>: public SigImpl::SignalHolder {
+template <typename Arg1>
+class Signal<Arg1, SigImpl::EmptyArg, SigImpl::EmptyArg>:
+        public SigImpl::SignalTemplate<Arg1, SigImpl::EmptyArg, SigImpl::EmptyArg> {
 public:
-    void emit(Arg1 arg) {
-        begin_emitting();
-        for ( Iterator it = begin(); it != end(); ++it ) {
-            if(*it)
-                static_cast<SigImpl::SlotBase1<ReturnType, Arg1> &>(**it)(arg);
-        }
-        end_emitting();
-    }
-
-    template<typename Functor>
-    SlotID connect(const Functor& functor) {
-        return SignalHolder::connect(SlotPtr(
-                        new SigImpl::Slot1<ReturnType, Arg1, Functor>(functor)
-                    ));
+    void emit(Arg1 arg1) {
+        SigImpl::SignalTemplate<Arg1, SigImpl::EmptyArg, SigImpl::EmptyArg>
+            ::emit_(arg1, SigImpl::EmptyArg(), SigImpl::EmptyArg());
     }
 };
 
 /// Specialization for no arguments.
-template <typename ReturnType>
-class Signal<ReturnType, SigImpl::EmptyArg, SigImpl::EmptyArg, SigImpl::EmptyArg>: public SigImpl::SignalHolder {
+template <>
+class Signal<SigImpl::EmptyArg, SigImpl::EmptyArg, SigImpl::EmptyArg>:
+        public SigImpl::SignalTemplate<SigImpl::EmptyArg, SigImpl::EmptyArg, SigImpl::EmptyArg> {
 public:
     void emit() {
-        begin_emitting();
-        for ( Iterator it = begin(); it != end(); ++it ) {
-            if(*it)
-                static_cast<SigImpl::SlotBase0<ReturnType> &>(**it)();
-        }
-        end_emitting();
-    }
-
-    template<typename Functor>
-    SlotID connect(const Functor& functor) {
-        return SignalHolder::connect(SlotPtr(
-                        new SigImpl::Slot0<ReturnType, Functor>(functor)
-                    ));
+        SigImpl::SignalTemplate<SigImpl::EmptyArg, SigImpl::EmptyArg, SigImpl::EmptyArg>
+            ::emit_(SigImpl::EmptyArg(), SigImpl::EmptyArg(), SigImpl::EmptyArg());
     }
 };
 
diff --git a/src/FbTk/Slot.hh b/src/FbTk/Slot.hh
index 3daca4e..ea7ee2f 100644
--- a/src/FbTk/Slot.hh
+++ b/src/FbTk/Slot.hh
@@ -22,81 +22,72 @@
 #ifndef FBTK_SLOT_HH
 #define FBTK_SLOT_HH
 
+#include "RefCount.hh"
+
 namespace FbTk {
 
 /// \namespace Implementation details for signals, do not use anything in this namespace
 namespace SigImpl {
 
+struct EmptyArg {};
+
 class SlotBase {
 public:
     virtual ~SlotBase() {}
 };
 
-template<typename ReturnType>
-class SlotBase0: public SlotBase {
+template<typename Arg1, typename Arg2, typename Arg3>
+class SlotTemplate: public SlotBase {
 public:
-    virtual ReturnType operator()() = 0;
+    virtual void operator()(Arg1, Arg2, Arg3) = 0;
 };
 
-template<typename ReturnType, typename Functor>
-class Slot0: public SlotBase0<ReturnType> {
+template<typename Arg1, typename Arg2, typename Arg3, typename Functor>
+class Slot: public SlotTemplate<Arg1, Arg2, Arg3> {
 public:
-    virtual ReturnType operator()() { return m_functor(); }
+    virtual void operator()(Arg1 arg1, Arg2 arg2, Arg3 arg3)
+    { m_functor(arg1, arg2, arg3); }
 
-    Slot0(Functor functor) : m_functor(functor) {}
+    Slot(Functor functor) : m_functor(functor) {}
 
 private:
     Functor m_functor;
 };
 
-template<typename ReturnType, typename Arg1>
-class SlotBase1: public SlotBase {
-public:
-    virtual ReturnType operator()(Arg1) = 0;
-};
-
-template<typename ReturnType, typename Arg1, typename Functor>
-class Slot1: public SlotBase1<ReturnType, Arg1> {
+// specialization for two arguments
+template<typename Arg1, typename Arg2, typename Functor>
+class Slot<Arg1, Arg2, EmptyArg, Functor>: public SlotTemplate<Arg1, Arg2, EmptyArg> {
 public:
-    virtual ReturnType operator()(Arg1 arg1) { return m_functor(arg1); }
+    virtual void operator()(Arg1 arg1, Arg2 arg2, EmptyArg)
+    { m_functor(arg1, arg2); }
 
-    Slot1(Functor functor) : m_functor(functor) {}
+    Slot(Functor functor) : m_functor(functor) {}
 
 private:
     Functor m_functor;
 };
 
-template<typename ReturnType, typename Arg1, typename Arg2>
-class SlotBase2: public SlotBase {
-public:
-    virtual ReturnType operator()(Arg1, Arg2) = 0;
-};
-
-template<typename ReturnType, typename Arg1, typename Arg2, typename Functor>
-class Slot2: public SlotBase2<ReturnType, Arg1, Arg2> {
+// specialization for one argument
+template<typename Arg1, typename Functor>
+class Slot<Arg1, EmptyArg, EmptyArg, Functor>: public SlotTemplate<Arg1, EmptyArg, EmptyArg> {
 public:
-    virtual ReturnType operator()(Arg1 arg1, Arg2 arg2) { return m_functor(arg1, arg2); }
+    virtual void operator()(Arg1 arg1, EmptyArg, EmptyArg)
+    { m_functor(arg1); }
 
-    Slot2(Functor functor) : m_functor(functor) {}
+    Slot(Functor functor) : m_functor(functor) {}
 
 private:
     Functor m_functor;
 };
 
-template<typename ReturnType, typename Arg1, typename Arg2, typename Arg3>
-class SlotBase3: public SlotBase {
-public:
-    virtual ReturnType operator()(Arg1, Arg2, Arg3) = 0;
-    virtual ~SlotBase3() {}
-};
-
-template<typename ReturnType, typename Arg1, typename Arg2, typename Arg3, typename Functor>
-class Slot3: public SlotBase3<ReturnType, Arg1, Arg2, Arg3> {
+// specialization for no arguments
+template<typename Functor>
+class Slot<EmptyArg, EmptyArg, EmptyArg, Functor>: public SlotTemplate<EmptyArg, EmptyArg, EmptyArg> {
 public:
-    virtual ReturnType operator()(Arg1 arg1, Arg2 arg2, Arg3 arg3)
-    { return m_functor(arg1, arg2, arg3); }
+    virtual void operator()(EmptyArg, EmptyArg, EmptyArg)
+    { m_functor(); }
 
-    Slot3(Functor functor) : m_functor(functor) {}
+    Slot(Functor functor) : m_functor(functor) {}
 
 private:
     Functor m_functor;
@@ -106,4 +97,5 @@ private:
 
 } // namespace FbTk
 
+
 #endif // FBTK_SLOT_H
diff --git a/src/FbTk/Theme.hh b/src/FbTk/Theme.hh
index c700f9b..a0f2717 100644
--- a/src/FbTk/Theme.hh
+++ b/src/FbTk/Theme.hh
@@ -107,13 +107,13 @@ public:
     template <typename T>
     void remove(ThemeItem<T> &item);
     virtual bool fallback(ThemeItem_base &) { return false; }
-    Signal<void> &reconfigSig() { return m_reconfig_sig; }
+    Signal<> &reconfigSig() { return m_reconfig_sig; }
 
 private:
     const int m_screen_num;
 
     ItemList m_themeitems;
-    Signal<void> m_reconfig_sig;
+    Signal<> m_reconfig_sig;
 };
 
 /// Proxy interface for themes, so they can be substituted dynamically
@@ -122,7 +122,7 @@ class ThemeProxy {
 public:
     virtual ~ThemeProxy() { }
 
-    virtual Signal<void> &reconfigSig() = 0;
+    virtual Signal<> &reconfigSig() = 0;
 
     virtual BaseTheme &operator *() = 0;
     virtual const BaseTheme &operator *() const = 0;