release: 1.5.29

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

diff --git a/lily/include/music-iterator.hh b/lily/include/music-iterator.hh
index 2f9c6cf7cc887f3109c0b8353a75972315dbc396..7bcb40fc8ac1965252637352e1f48999648d9bb2 100644 (file)
--- a/lily/include/music-iterator.hh
+++ b/lily/include/music-iterator.hh
@@ -3,7 +3,7 @@
 
   source file of the GNU LilyPond music typesetter
 
-  (c)  1997--2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c)  1997--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
 */
 
 
@@ -15,6 +15,7 @@
 #include "moment.hh"
 #include "virtual-methods.hh"
 #include "interpretation-context-handle.hh"
+#include "cxx-function-smob.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.
 
@@ -35,19 +37,27 @@
     thus changing the state of the interpretation context.
 
   get_music (M) -- return all events starting at M (pre: no events
-    before M).  Side effects:
+    before M). No side-effects
 
-    * This removes all events at M from the pending queue.
+  skip (M) -- remove all events starting before M (leave the ones that
+    start M).  no side-effects on interpretation context
 
-  Because next (M) is rolled into process () as a side effect,
-  we need to roll next (M) into get_music too.  Urg.
-    
+
+  TODO:
+
+  merge pending_moment and process?
+  
 */
 class Music_iterator
 {
+protected:
+  Moment music_length_;
+  Moment start_mom_;
 public:
   VIRTUAL_COPY_CONS (Music_iterator);
 
+  Moment music_length_mom () const;
+  Moment music_start_mom () const;
   Music_iterator ();
   Music_iterator (Music_iterator const&);
   virtual ~Music_iterator ();
@@ -57,7 +67,7 @@ public:
      then its children. Returns the iterator that succeeded
   */
   Music_iterator *  try_music (Music  *) const;
-
+  
   /**
     The translation unit that we this iterator is reporting  to now.
    */
@@ -75,16 +85,15 @@ public:
   virtual bool ok () const;
   virtual SCM get_music (Moment until)const;
   virtual void process (Moment until);
+  virtual void skip (Moment until);
 
   /**
     Construct sub-iterators, and set the translator to 
     report to.
    */
   virtual void construct_children ();
-
-protected:
-  Music  * music_l_;
-
+  static SCM constructor_cxx_function;
+  
   /**
     Get an iterator for MUS, inheriting the translation unit from THIS.
    */
@@ -92,8 +101,38 @@ protected:
 
   virtual Music_iterator* try_music_in_children (Music *) const;
 
+  Music * music_l () const;
 private:
   Interpretation_context_handle handle_;
+  Music  * music_l_;
 };
 
+
+/*
+  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