Issue 4835: Move Callback_wrapper class to separate file and simplify

[lilypond.git] / lily / include / translator.hh

diff --git a/lily/include/translator.hh b/lily/include/translator.hh
index 54a7f318f77d32c921c82faeec431a69f6deac63..118220772ab72b758ea467f67e616bbff6946230 100644 (file)
--- a/lily/include/translator.hh
+++ b/lily/include/translator.hh
@@ -28,35 +28,11 @@
 #include "std-vector.hh"
 #include "protected-scm.hh"
 
-/*
-  Each translator class has a static list of listener records. Each
-  record makes one explains how to register one of the class's stream event
-  listeners to a context.
-*/
-typedef struct translator_listener_record
-{
-  Listener (*get_listener_) (void *, SCM event_class);
-  SCM event_class_;
-  struct translator_listener_record *next_;
-
-  translator_listener_record ()
-  {
-    next_ = 0;
-    event_class_ = SCM_EOL;
-    get_listener_ = 0;
-  }
-
-} translator_listener_record;
-
-#define TRANSLATOR_DECLARATIONS_NO_LISTENER(NAME)                       \
+#define TRANSLATOR_FAMILY_DECLARATIONS(NAME)                            \
   public:                                                               \
-  NAME ();                                                              \
   VIRTUAL_COPY_CONSTRUCTOR (Translator, NAME);                          \
-  static SCM static_description_;                                       \
   static Drul_array<vector<Acknowledge_information> > acknowledge_static_array_drul_; \
-  virtual void fetch_precomputable_methods (Callback methods[]); \
-  virtual SCM static_translator_description () const;                   \
-  virtual SCM translator_description () const;                          \
+  virtual void fetch_precomputable_methods (Callback methods[]);        \
   static Grob_info_callback static_get_acknowledger (SCM sym);          \
   static Grob_info_callback static_get_end_acknowledger(SCM);           \
   virtual Grob_info_callback get_acknowledger (SCM sym)                 \
@@ -66,15 +42,25 @@ typedef struct translator_listener_record
   virtual Grob_info_callback get_end_acknowledger (SCM sym)             \
   {                                                                     \
     return static_get_end_acknowledger (sym);                           \
-  } \
+  }                                                                     \
   /* end #define */
 
+/*
+  Each translator class has a static alist of event class symbols
+  mapping to callbacks that are called with a translator instance and
+  a stream event when an event of the appropriate event class is
+  announced in a context.
+*/
+
 #define TRANSLATOR_DECLARATIONS(NAME)                                   \
-  TRANSLATOR_DECLARATIONS_NO_LISTENER(NAME)                             \
-private:                                                                \
-  static translator_listener_record *listener_list_;                    \
+  TRANSLATOR_FAMILY_DECLARATIONS(NAME)                                  \
+  static SCM static_description_;                                       \
+  static Protected_scm listener_list_;                                  \
 public:                                                                 \
-  virtual translator_listener_record *get_listener_list () const        \
+  NAME ();                                                              \
+  virtual SCM static_translator_description () const;                   \
+  virtual SCM translator_description () const;                          \
+  virtual SCM get_listener_list () const                                \
   {                                                                     \
     return listener_list_;                                              \
   }                                                                     \
@@ -84,10 +70,7 @@ public:                                                                 \
 public:                                                 \
 inline void listen_ ## m (Stream_event *);              \
 /* Should be private */                                 \
-static void _internal_declare_ ## m ();                 \
-private:                                                \
- static Listener _get_ ## m ## _listener (void *, SCM); \
-void _listen_scm_ ## m (SCM);
+static void _internal_declare_ ## m ();
 
 #define DECLARE_ACKNOWLEDGER(x) public : void acknowledge_ ## x (Grob_info); protected:
 #define DECLARE_END_ACKNOWLEDGER(x) public : void acknowledge_end_ ## x (Grob_info); protected:
@@ -112,8 +95,8 @@ public:
   // as the timing of Engraver is exercised from within Translator
   typedef void (Translator::*Grob_info_callback) (Grob_info);
   typedef void (Translator::*Callback) (void);
-  int print_smob (SCM, scm_print_state *);
-  SCM mark_smob ();
+  int print_smob (SCM, scm_print_state *) const;
+  SCM mark_smob () const;
   static const char type_p_name_[];
   virtual ~Translator ();
 private:
@@ -150,14 +133,24 @@ public:
 protected:                      // should be private.
   Context *daddy_context_;
   void protect_event (SCM ev);
+
+  template <class T, void (T::*callback)(Stream_event *)>
+  static SCM trampoline (SCM target, SCM event)
+  {
+    T *t = unsmob<T> (target);
+    LY_ASSERT_SMOB (T, target, 1);
+    LY_ASSERT_SMOB (Stream_event, event, 2);
+
+    t->protect_event (event);
+    (t->*callback) (unsmob<Stream_event> (event));
+    return SCM_UNSPECIFIED;
+  }
+
   virtual void derived_mark () const;
-  static void add_translator_listener (translator_listener_record **listener_list,
-                                       translator_listener_record *r,
-                                       Listener (*get_listener) (void *, SCM),
-                                       const char *ev_class);
+  static SCM event_class_symbol (const char *ev_class);
   SCM static_translator_description (const char *grobs,
                                      const char *desc,
-                                     translator_listener_record *listener_list,
+                                     SCM listener_list,
                                      const char *read,
                                      const char *write) const;