release: 1.3.138

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

diff --git a/lily/include/music-iterator.hh b/lily/include/music-iterator.hh
index e7bda4c554fc5d8f3b82027a91ac21fcdd30b9a3..4041b5d028f46cd442b269108b762f1c7b86afdc 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--1998 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c)  1997--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
 */
 
 
@@ -11,43 +11,128 @@
 #define MUSIC_ITERATOR_HH
 
 #include "lily-proto.hh"
-#include "plist.hh"
 #include "array.hh"
 #include "moment.hh"
 #include "virtual-methods.hh"
+#include "interpretation-context-handle.hh"
+#include "cxx-function-smob.hh"
 
-class Music_iterator {
-  Array<Translator_group*>report_to_l_arr_;
-  void push_translator (Translator_group*);
-  void pop_translator();
-protected:
-  Music const * music_l_;
-  bool first_b_;
-  virtual void do_print() const;
+/** 
+  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.
+
+  
+  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:
     
-  virtual Translator_group* get_req_translator_l();
-  Music_iterator* get_iterator_p (Music const*) const;
-  void set_translator (Translator_group*);
-  virtual void do_process_and_next (Moment until);
-  void inherit_info (Music_iterator const *parent);
+    * This removes all events at M from the pending queue.
+
+    * Typically this reports the music to an interpretation context,
+    thus changing the state of the interpretation context.
+
+  get_music (M) -- return all events starting at M (pre: no events
+    before M). No side-effects
+
+  skip (M) -- remove all events starting before M (leave the ones that
+    start M).  no side-effects on interpretation context
+
+
+  TODO:
+
+  merge pending_moment and process?
+  
+*/
+class Music_iterator
+{
+protected:
+  Moment music_length_;
+
 public:
-  Translator_group*report_to_l() const;
-  DECLARE_MY_RUNTIME_TYPEINFO;
- 
-  static Music_iterator* static_get_iterator_p (Music const*,Translator_group*);
-  Music_iterator();
-    
-  virtual Moment next_moment() const;
-  virtual bool ok() const;
-  virtual ~Music_iterator();
-  void process_and_next (Moment until);
+  VIRTUAL_COPY_CONS (Music_iterator);
+
+  Moment music_length_mom () const;
+  Music_iterator ();
+  Music_iterator (Music_iterator const&);
+  virtual ~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;
+  
+  /**
+    The translation unit that we this iterator is reporting  to now.
+   */
+  Translator_group* report_to_l () const;
+
+  void set_translator (Translator_group*);
+  
+  /** 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 * mus);
+  void init_translator (Music  *, Translator_group *); 
+
+  virtual Moment pending_moment () const;
+  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
+    report to.
+   */
+  virtual void construct_children ();
+  static SCM constructor_cxx_function;
+  
+protected:
+  Music  * music_l_;
+
+  /**
+    Get an iterator for MUS, inheriting the translation unit from THIS.
    */
-  virtual void construct_children();
-  void print() const;
+  Music_iterator* get_iterator_p (Music *) const;
+
+  virtual Music_iterator* try_music_in_children (Music *) const;
+
+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