[Emacs-diffs] /srv/bzr/emacs/emacs-24 r108026: Improve commentary to 'struct it' in src/dispextern.h.

[Eli Zaretskii]

------------------------------------------------------------
revno: 108026
committer: Eli Zaretskii <address@hidden>
branch nick: emacs-24
timestamp: Fri 2012-06-01 12:14:07 +0300
message:
  Improve commentary to 'struct it' in src/dispextern.h.
modified:
  src/dispextern.h

=== modified file 'src/dispextern.h'
--- a/src/dispextern.h  2012-03-26 05:43:05 +0000
+++ b/src/dispextern.h  2012-06-01 09:14:07 +0000
@@ -2208,7 +2208,11 @@
   struct display_pos current;
 
   /* Total number of overlay strings to process.  This can be >
-     OVERLAY_STRING_CHUNK_SIZE.  */
+     OVERLAY_STRING_CHUNK_SIZE.  Value is dependable only when
+     current.overlay_string_index >= 0.  Use the latter to determine
+     whether an overlay string is being iterated over, because
+     n_overlay_strings can be positive even when we are not rendering
+     an overlay string.  */
   int n_overlay_strings;
 
   /* The charpos where n_overlay_strings was calculated.  This should
@@ -2227,7 +2231,8 @@
 
   /* If non-nil, a Lisp string being processed.  If
      current.overlay_string_index >= 0, this is an overlay string from
-     pos.  */
+     pos.  Use STRINGP(it.string) as a test for whether we are
+     rendering a string or something else; do NOT use BUFFERP(it.object).  */
   Lisp_Object string;
 
   /* If non-nil, we are processing a string that came
@@ -2416,6 +2421,9 @@
      and continuation glyphs, or blanks that extend each line to the
      edge of the window on a TTY.
 
+     Do NOT use !BUFFERP (it.object) as a test whether we are
+     iterating over a string; use STRINGP (it.string) instead.
+
      Position is the current iterator position in object.  */
   Lisp_Object object;
   struct text_pos position;