Streamline application class registration

[libs/core.git] / source / core / application.h

diff --git a/source/core/application.h b/source/core/application.h
index 38df732f1a5779782566d249b701a19ca99011a2..305fbfe34661967a3d8dbeca46ed30f2f9c1596f 100644 (file)
--- a/source/core/application.h
+++ b/source/core/application.h
@@ -17,29 +17,22 @@ member of type RegApp<MainClass>.
 class Application
 {
 protected:
-       class RegBase
+       class Starter
        {
-       public:
-               virtual Application *create_app(int, char **)=0;
-               virtual void usage(const char *, const char *, bool)=0;
-               virtual ~RegBase() { }
        protected:
-               RegBase();
-       };
-
-       template<typename T>
-       class RegApp: public RegBase
-       {
+               Starter();
        public:
-               Application *create_app(int argc, char **argv) { return new T(argc, argv); }
-               void usage(const char *r, const char *a, bool b) { T::usage(r, a, b); }
+               virtual ~Starter() { }
+
+               virtual Application *create_app(int, char **) = 0;
+               virtual void usage(const char *, const char *, bool) = 0;
        };
 
        bool done;
        int exit_code;
 
 private:
-       static RegBase *reg_app_;
+       static Starter *starter_;
        static Application *app_;
        static void *data_;
 
@@ -60,11 +53,32 @@ protected:
        virtual void sighandler(int) { }
 private:
        static void sighandler_(int);
+};
 
        Application(const Application &);
        Application &operator=(const Application &);
+
+template<typename T>
+class RegisteredApplication: public Application
+{
+private:
+       class Starter: public Application::Starter
+       {
+       public:
+               Application *create_app(int argc, char **argv) { return new T(argc, argv); }
+               void usage(const char *r, const char *a, bool b) { T::usage(r, a, b); }
+       };
+
+       static Starter starter_;
+
+protected:
+       // Force the starter into existence
+       RegisteredApplication() { (void)starter_; }
 };
 
+template<typename T>
+typename RegisteredApplication<T>::Starter RegisteredApplication<T>::starter_;
+
 } // namespace Msp
 
 #endif