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>
*/
#include "moment.hh"
#include "virtual-methods.hh"
#include "interpretation-context-handle.hh"
+#include "cxx-function-smob.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.
+/**
+ 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.
- 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_;
+
+ ok () -- events left ?
-protected:
- bool playback_b_; // Should use SCMs
+ pending_mom () -- time tag of the next event to be processed.
+ PRECONDITION: this->ok () holds.
- Music const * music_l_;
+ 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.
- /// ugh. JUNKME
- bool first_b_;
+ * Typically this reports the music to an interpretation context,
+ thus changing the state of the interpretation context.
- /**
- 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;
-
- /**
- Find a bottom notation context to deliver requests to.
- */
- virtual Translator_group* get_req_translator_l();
+ get_music (M) -- return all events starting at M (pre: no events
+ before M). No side-effects
- /**
- Get an iterator for MUS, inheriting the translation unit from THIS.
- */
- Music_iterator* get_iterator_p (Music const*mus) const;
+ skip (M) -- remove all events starting before M (leave the ones that
+ start M). no side-effects on 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_;
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 ();
/**
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;
+ 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. Repeated music can be fully
- unfolded by setting PLAYING */
- static Music_iterator* static_get_iterator_p (Music const* mus, bool playing);
- void init_translator (Music const *, Translator_group *);
-
- 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();
-
+ an accompanying translation unit
+ */
+ static Music_iterator* static_get_iterator_p (Music * mus);
+ void init_translator (Music *, Translator_group *);
- ///Report all musical information that occurs between now and UNTIL
- void process_and_next (Moment until);
+ 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.
*/
- virtual void construct_children();
- void print() const;
+ virtual void construct_children ();
+ static SCM constructor_cxx_function;
+
+ /**
+ Get an iterator for MUS, inheriting the translation unit from THIS.
+ */
+ Music_iterator* get_iterator_p (Music *) const;
+
+ 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
projects / lilypond.git / blobdiff