patch::: 1.3.108.jcn1

[lilypond.git] / lily / include / music-iterator.hh

diff --git a/lily/include/music-iterator.hh b/lily/include/music-iterator.hh
index 1709a5d8e81bec1c212171f594cd8b45438904fd..39919db96b759b034b66ef1526b2f92ca9dde9d8 100644 (file)
--- a/lily/include/music-iterator.hh
+++ b/lily/include/music-iterator.hh
@@ -15,6 +15,7 @@
 #include "moment.hh"
 #include "virtual-methods.hh"
 #include "interpretation-context-handle.hh"
+#include "music-iterator-ctor.hh"
 
 /** 
   Conceptually a music-iterator operates on a queue of musical events
@@ -25,9 +26,10 @@
   ok () -- events left ?
 
   pending_mom () -- time tag of the next event to be processed.
+    PRECONDITION: this->ok() holds.
   
-  process (M) -- process all at M (Precondition: no events exist before
-    M).  Side-effects:
+  process (M) -- process all at M (Precondition: no events exist
+    before M, this->ok() holds).  Side-effects:
     
     * This removes all events at M from the pending queue.
 
@@ -43,7 +45,7 @@
 
   TODO:
 
-  merge pending_moment and process.
+  merge pending_moment and process?
   
 */
 class Music_iterator
@@ -55,8 +57,6 @@ public:
   VIRTUAL_COPY_CONS (Music_iterator);
 
   Moment music_length_mom () const;
-
-  
   Music_iterator ();
   Music_iterator (Music_iterator const&);
   virtual ~Music_iterator ();
@@ -91,7 +91,8 @@ public:
     report to.
    */
   virtual void construct_children ();
-
+  static SCM constructor_cxx_function;
+  
 protected:
   Music  * music_l_;
 
@@ -106,4 +107,32 @@ private:
   Interpretation_context_handle handle_;
 };
 
+
+/*
+  implement Class::constructor, a SCM function that
+  returns an encapsulated factory function.
+ */
+#define IMPLEMENT_CTOR_CALLBACK(Class)         \
+static void *                                          \
+Class ## _ctor (SCM)                           \
+{                                              \
+  return new Class ;                           \
+}                                              \
+SCM Class :: constructor_cxx_function;\
+void                                           \
+Class ## _constructor_init()                           \
+{                                              \
+  SCM s = smobify_cxx_function (& Class ## _ctor);     \
+  scm_permanent_object (s);\
+  gh_define (#Class "::constructor", s);\
+  Class :: constructor_cxx_function = s;\
+}\
+ADD_SCM_INIT_FUNC(Class ## _ctor_init, Class ## _constructor_init); 
+
+ 
+
+
+
+
+
 #endif // MUSIC_ITERATOR_HH