+ Drul_array<bool> expansions (false, false);
+ if (at (LEFT).tone_pitch () > p.tone_pitch ())
+ {
+ at (LEFT) = p;
+ expansions [LEFT] = true;
+ }
+ if (at (RIGHT).tone_pitch () < p.tone_pitch ())
+ {
+ at (RIGHT) = p;
+ expansions [RIGHT] = true;
+ }
+ return expansions;
+}
+
+Pitch_lexicographic_interval::Pitch_lexicographic_interval (Pitch p1, Pitch p2)
+{
+ at (LEFT) = p1;
+ at (RIGHT) = p2;
+}
+
+Pitch_lexicographic_interval::Pitch_lexicographic_interval ()
+{
+ at (LEFT) = Pitch (100, 0);
+ at (RIGHT) = Pitch (-100, 0);
+}
+
+bool
+Pitch_lexicographic_interval::is_empty () const
+{
+ return at (LEFT) > at (RIGHT);
+}
+
+Drul_array<bool>
+Pitch_lexicographic_interval::add_point (Pitch p)
+{
+ Drul_array<bool> expansions (false, false);
+ if (at (LEFT) > p)
+ {
+ at (LEFT) = p;
+ expansions [LEFT] = true;
+ }
+ if (at (RIGHT) < p)
+ {
+ at (RIGHT) = p;
+ expansions [RIGHT] = true;
+ }
+ return expansions;