X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Finclude%2Fmusic-iterator.hh;h=5622e1660184976d52cc2255b2ce937bcba699c0;hb=94b46751bb219ecfe55543c4030c4dd2d9c2ca74;hp=f7d9c061e378160b750034b6ecfe96f8c2c7c9d0;hpb=339ea28cd7e4f8a1c1ca7c1d4dfe803a3f4c03e6;p=lilypond.git

diff --git a/lily/include/music-iterator.hh b/lily/include/music-iterator.hh
index f7d9c061e3..5622e16601 100644
--- 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--1999 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c) 1997--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
 */
 
 
@@ -15,90 +15,119 @@
 #include "moment.hh"
 #include "virtual-methods.hh"
 #include "interpretation-context-handle.hh"
+#include "smobs.hh"
 
-/** Walk through music and deliver music to translation units, synced
-  in time.  This class provides both the implementation of the shared
-  code, and the public interface.
+/**
+   ---
 
-  Derived classes should only have a public constructor.
-  The state of an iterator would be the intersection of the particular music 
-  construct with one point in musical time.
- */
-class Music_iterator {
-  Interpretation_context_handle handle_;
+   Music_iterator is an object type that traverses the Music structure and
+   reports the events it finds to interpretation contexts. It is not yet
+   user-serviceable.
 
-protected:
-  Music const * music_l_;
 
-  /// ugh. JUNKME
-  bool first_b_;
+   ---
+	
+  Conceptually a music-iterator operates on a queue of musical events
+  that are pending. This queue does not actually exist, but it is a
+  way of viewing and traversing music-expressions.
 
-  /**
-    Do the actual printing.  This should be overriden in derived classes.  It 
-    is called by #print#, in the public interface
-   */
-  virtual void do_print() const;
+  
+  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, this->ok () holds).  Side-effects:
     
-  /**
-    Find a bottom notation context to deliver requests to.
-   */
-  virtual Translator_group* get_req_translator_l();
+    * This removes all events at M from the pending queue.
 
-  /**
-    Get an iterator for MUS, inheriting the translation unit from THIS.
-   */
-  Music_iterator* get_iterator_p (Music const*mus) const;
+    * Typically this reports the music to an interpretation context,
+    thus changing the state of the interpretation context.
 
-  /** Do the actual move.  This should be overriden in derived
-    classes.  It is called by #process_and_next#, the public interface 
-    */
-  virtual void do_process_and_next (Moment until);
 
+  TODO:
 
-  virtual Music_iterator* try_music_in_children (Music const *) const;
+  merge pending_moment and process?
   
+*/
+class Music_iterator
+{
+protected:
+  Moment music_length_;
+  Moment start_mom_;
+
+  DECLARE_SMOBS (Music_iterator,dummy);
+  Music_iterator (Music_iterator const&);
 public:
+  
+  Moment music_get_length () const;
+  virtual Moment music_start_mom () const;
+  Music_iterator ();
 
   /**
      Do the reporting.  Will try MUSIC_L_ in its own translator first,
      then its children. Returns the iterator that succeeded
   */
-  Music_iterator *  try_music (Music const *) const;
-
+  Music_iterator *  try_music (Music  *) const;
+  
   /**
     The translation unit that we this iterator is reporting  to now.
    */
-  Translator_group*report_to_l() const;
+  Context * get_outlet () const;
 
-  void set_translator (Translator_group*);
+  void set_translator (Context *);
   
   /** Get an iterator matching the type of MUS, and use TRANS to find
     an accompanying translation unit
    */
-  static Music_iterator* static_get_iterator_p (Music const* mus);
-  void init_translator (Music const *, Translator_group *); 
-
-  Music_iterator();
-    
-  ///  Find the next interesting point in time.
-  virtual Moment next_moment() const;
+  static SCM get_static_get_iterator (Music * mus);
+  void init_translator (Music  *, Context *); 
+  void quit ();
+  void substitute_outlet (Context * from, Context *to);
+  virtual void derived_substitute (Context *, Context *);
+  virtual Moment pending_moment () const;
+  virtual bool ok () const;
+
+  virtual bool run_always () const; 
+  virtual void process (Moment until);
+  virtual void derived_mark ()const;
+  virtual void construct_children ();
+  
+  /**
+    Construct sub-iterators, and set the translator to 
+    report to.
+   */
 
+  DECLARE_SCHEME_CALLBACK(constructor, ());
+  
+  /**
+    Get an iterator for MUS, inheriting the translation unit from THIS.
+   */
+  SCM get_iterator (Music *) const;
 
-  ///Are we finished with this piece of music?
-  virtual bool ok() const;
+  virtual Music_iterator* try_music_in_children (Music *) const;
 
-  virtual ~Music_iterator();
+  Music * get_music () const;
+protected:
+  virtual void do_quit();
+private:
+  Interpretation_context_handle handle_;
+  Music  * music_;
+};
 
 
-  ///Report all musical information that occurs between now and UNTIL
-  void process_and_next (Moment until);
+#define IMPLEMENT_CTOR_CALLBACK(Class)		\
+LY_DEFINE_MEMBER_FUNCTION(Class,constructor, #Class "::constructor",\
+	  0,0,0,\
+	  (),\
+	  "Construct a @code{" #Class "} music iterator")\
+{						\
+  SCM val = (new Class)->self_scm();   \
+  scm_gc_unprotect_object (val);\
+  return val ;				\
+}						\
 
-  /**
-    Construct sub-iterators, and set the translator to 
-    report to.
-   */
-  virtual void construct_children();
-  void print() const;
-};
+DECLARE_UNSMOB(Music_iterator, iterator);
 
 #endif // MUSIC_ITERATOR_HH