Abstract method to return the value of this variable.
Value comparisons (as distinct from variable pointer equality)
If true then Diff objects will return this as their variable even when the value indicates it is not "present".
(Changed in version 2.9.0) The behavior of
scanRight has changed. The previous behavior can be reproduced with scanRight.reverse.
(Changed in version 2.9.0)
transpose throws an
IllegalArgumentException if collections are not uniformly sized.