Add some assertions.

git-svn-id: svn://localhost/ardour2/branches/3.0@9411 d708f5d6-7413-0410-9779-e7cbd77b26cf

libs/ardour/beats_frames_converter.cc

@@ -27,6 +27,8 @@ namespace ARDOUR {
 framecnt_t
 BeatsFramesConverter::to (double beats) const
 {
+	assert (beats >= 0);
+	
 	return _tempo_map.framepos_plus_bbt (_origin_b, Timecode::BBT_Time(beats)) - _origin_b;
 }
 

libs/timecode/src/bbt_time.cc

@@ -17,6 +17,7 @@
 */
 
 #include <cmath>
+#include <cassert>
 
 #include "timecode/bbt_time.h"
 
@@ -31,6 +32,8 @@ BBT_Time::BBT_Time (double dbeats)
            always be zero.
         */
 
+	assert (dbeats >= 0);
+
         bars = 0;
         beats = rint (floor (dbeats));
         ticks = rint (floor (BBT_Time::ticks_per_beat * fmod (dbeats, 1.0)));