source file of the GNU LilyPond music typesetter
- (c) 1997--1999 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+ (c) 1997--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
*/
#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 "smobs.hh"
-/** Walk through music and deliver music to translation units, synced
- in time. This classa 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_;
- bool first_b_;
- /**
- 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;
+ ---
+
+ 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:
- /**
- 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;
- void set_translator (Translator_group*);
+ * Typically this reports the music to an interpretation context,
+ thus changing the state of the interpretation context.
+
+ get_pending_events (M) -- return all events starting at M (pre: no events
+ before M). No side-effects
- /** Do the actual reporting. 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);
+ 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_;
+ Moment start_mom_;
+
+ DECLARE_SMOBS (Music_iterator,dummy);
public:
+ VIRTUAL_COPY_CONS (Music_iterator);
+
+ Moment music_length_mom () const;
+ Moment music_start_mom () const;
+ Music_iterator ();
+ Music_iterator (Music_iterator const&);
+ /**
+ 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;
+ Translator_group* report_to () 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 const* mus,Translator_group* trans);
-
- Music_iterator();
-
- /// Find the next interesting point in time.
- virtual Moment next_moment() const;
-
- ///Are we finished with this piece of music?
- virtual bool ok() const;
-
- virtual ~Music_iterator();
-
-
- ///Report all musical information that occurs between now and UNTIL
- void process_and_next (Moment until);
+ static SCM get_static_get_iterator (Music * mus);
+ void init_translator (Music *, Translator_group *);
+void quit ();
+
+ virtual Moment pending_moment () const;
+ virtual bool ok () const;
+ virtual SCM get_pending_events (Moment until)const;
+ virtual void process (Moment until);
+ virtual void skip (Moment until);
+ virtual void derived_mark ()const;
+ virtual void construct_children ();
+
/**
Construct sub-iterators, and set the translator to
report to.
*/
- virtual void construct_children();
- void print() const;
+
+ DECLARE_SCHEME_CALLBACK(constructor, ());
+
+ /**
+ Get an iterator for MUS, inheriting the translation unit from THIS.
+ */
+ SCM get_iterator (Music *) const;
+
+ virtual Music_iterator* try_music_in_children (Music *) const;
+
+ Music * get_music () const;
+protected:
+ virtual void do_quit();
+private:
+ Interpretation_context_handle handle_;
+ Music * music_;
};
+
+#define IMPLEMENT_CTOR_CALLBACK(Class) \
+LY_DEFINE_MEMBER_FUNCTION(Class,constructor, #Class "::constructor",\
+ 0,0,0,\
+ (),\
+ "Construct a " #Class " music iterator")\
+{ \
+ SCM val = (new Class)->self_scm(); \
+ scm_gc_unprotect_object (val);\
+ return val ; \
+} \
+
+DECLARE_UNSMOB(Music_iterator, iterator);
+
#endif // MUSIC_ITERATOR_HH
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