From: David Kastrup <dak@gnu.org>
Date: Tue, 7 Jul 2015 10:59:51 +0000 (+0200)
Subject: music-iterator.hh: add some comments
X-Git-Tag: release/2.19.24-1~5^2
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=d84eb031543189fa253a1705c312a16a66af9c16;p=lilypond.git

music-iterator.hh: add some comments
---

diff --git a/lily/include/music-iterator.hh b/lily/include/music-iterator.hh
index de53608ed5..214079d23a 100644
--- a/lily/include/music-iterator.hh
+++ b/lily/include/music-iterator.hh
@@ -75,6 +75,9 @@ private:
 
 public:
   Moment music_get_length () const;
+  // music_start_mom () is calculated relative to the time where the
+  // iterator occurs in the music stream, so it will usually be
+  // non-zero only for expressions starting with grace notes.
   Moment music_start_mom () const;
   Music_iterator ();
   void report_event (Music *);
@@ -89,6 +92,8 @@ public:
   virtual Moment pending_moment () const;
   virtual bool ok () const;
   virtual bool run_always () const;
+  // process is called with a time relative to the iterator start, so
+  // usually the last processed moment is the same as music_get_length.
   virtual void process (Moment until);
   virtual void derived_mark () const;
   virtual void construct_children ();