[LyX/master] Comment.

[Richard Kimberly Heck]

commit 986a55fd7e15e7a17f215a4bd9c1b0c9220c4861
Author: Richard Kimberly Heck <rikiheck at lyx.org>
Date:   Sun Apr 19 13:31:57 2020 -0400

    Comment.
---
 src/support/types.h |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/src/support/types.h b/src/support/types.h
index fc443dc..c9cf349 100644
--- a/src/support/types.h
+++ b/src/support/types.h
@@ -28,6 +28,9 @@ namespace lyx {
 	 */
 	// FIXME: should be unsigned, but needs to be signed for a while to
 	// hold the special value -1 that is used somewhere
+	// Specifically, TexRow::getDocIteratorsFromEntries uses negative pos
+	// the way Python does: counting from the end. So maybe this should just
+	// be signed.
 	// Note that the signed property is also used in loops counting to zero.
 	typedef ptrdiff_t  pos_type;