]> git.donarmstrong.com Git - lilypond.git/blobdiff - lily/include/translator.hh
Issue 4842/4: Replace Translator_method et al
[lilypond.git] / lily / include / translator.hh
index d342d3363cbcfb03c1159c1d57eb894f287a85d7..ad8765fd54c1bf902b83c14f12d0ef2c5795c6ef 100644 (file)
 #include "global-ctor.hh"
 #include "lily-proto.hh"
 #include "virtual-methods.hh"
+#include "callback.hh"
 #include "input.hh"             // for error reporting
 #include "smobs.hh"
 #include "std-vector.hh"
 #include "protected-scm.hh"
 
-struct Acknowledge_information
-{
-  SCM symbol_;
-  Engraver_void_function_engraver_grob_info function_;
-
-  Acknowledge_information ()
-  {
-    symbol_ = SCM_EOL;
-    function_ = 0;
-  }
-};
-
-/*
-  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)                       \
-private:                                                                \
+#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 (Translator_void_method_ptr methods[]); \
-  virtual SCM static_translator_description () const;                   \
-  virtual SCM translator_description () const;                          \
-  static Engraver_void_function_engraver_grob_info static_get_acknowledger (SCM sym); \
-  static Engraver_void_function_engraver_grob_info static_get_end_acknowledger(SCM); \
-  virtual Engraver_void_function_engraver_grob_info get_acknowledger (SCM sym) \
+  virtual void fetch_precomputable_methods (SCM methods[]);             \
+  DECLARE_TRANSLATOR_CALLBACKS (NAME);                                  \
+  TRANSLATOR_INHERIT (Translator)                                       \
+  static SCM static_get_acknowledger (SCM sym);                         \
+  static SCM static_get_end_acknowledger(SCM);                          \
+  virtual SCM get_acknowledger (SCM sym)                                \
   {                                                                     \
     return static_get_acknowledger (sym);                               \
   }                                                                     \
-  virtual Engraver_void_function_engraver_grob_info get_end_acknowledger (SCM sym) \
+  virtual SCM get_end_acknowledger (SCM sym)                            \
   {                                                                     \
     return static_get_end_acknowledger (sym);                           \
-  } \
+  }                                                                     \
+  /* end #define */
+
+#define TRANSLATOR_INHERIT(BASE)                                        \
+  using BASE::method_finder;                                            \
+  using BASE::ack_finder;
+
+#define DECLARE_TRANSLATOR_CALLBACKS(NAME)                              \
+  template <void (NAME::*mf)()>                                         \
+  static SCM method_finder () { return method_find_base<NAME, mf> (); } \
+  template <void (NAME::*callback)(Grob_info)>                          \
+  static SCM ack_finder () { return ack_find_base<NAME, callback> (); } \
   /* 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_;                    \
+  public:                                                               \
+  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_;                                              \
   }                                                                     \
@@ -97,10 +85,7 @@ public:                                                                 \
 public:                                                 \
 inline void listen_ ## m (Stream_event *);              \
 /* Should be private */                                 \
-static void _internal_declare_ ## m ();                 \
-private:                                                \
- static Listener _get_ ## m ## _listener (void *, SCM); \
-DECLARE_LISTENER (_listen_scm_ ## m);
+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:
@@ -120,8 +105,8 @@ enum Translator_precompute_index
 class Translator : public Smob<Translator>
 {
 public:
-  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:
@@ -130,6 +115,7 @@ private:
 public:
   Context *context () const { return daddy_context_; }
 
+  Translator ();
   Translator (Translator const &);
 
   SCM internal_get_property (SCM symbol) const;
@@ -153,25 +139,73 @@ public:
   Context *get_score_context () const;
   Global_context *get_global_context () const;
 
-  TRANSLATOR_DECLARATIONS (Translator);
+  DECLARE_CLASSNAME (Translator);
+  virtual Translator *clone () const = 0;
+  virtual void fetch_precomputable_methods (SCM methods[]) = 0;
+  virtual SCM get_listener_list () const = 0;
+  virtual SCM translator_description () const = 0;
+  virtual SCM get_acknowledger (SCM sym) = 0;
+  virtual SCM get_end_acknowledger (SCM sym) = 0;
 
 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;
+  }
+
+  template <class T, void (T::*mf)()>
+  static SCM
+  method_find_base () { return Callback0_wrapper::make_smob<T, mf> (); }
+
+  // Fallback for non-overriden callbacks for which &T::x degrades to
+  // &Translator::x
+  template <void (Translator::*)()>
+  static SCM
+  method_finder () { return SCM_UNDEFINED; }
+
+  // Overriden in Engraver.
+  template <class T, void (T::*callback)(Grob_info)>
+  static SCM
+  ack_find_base () { return SCM_UNDEFINED; }
+
+  template <void (Translator::*)(Grob_info)>
+  static SCM
+  ack_finder () { return SCM_UNDEFINED; }
+
   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;
 
   friend class Translator_group;
 };
 
+struct Acknowledge_information
+{
+  SCM symbol_;
+  SCM function_;
+
+  Acknowledge_information ()
+  {
+    symbol_ = SCM_EOL;
+    function_ = SCM_UNDEFINED;
+  }
+};
+
+
 void add_translator (Translator *trans);
 
 Translator *get_translator (SCM s);