Changes by: Aleksey Nogin (nogin at cs.caltech.edu)
Date: 1999-06-08 19:19:59 -0700 (Tue, 08 Jun 1999)
Revision: 2696
Log message:
Added a comsistent way of coming up with a new name for a variable that needs to be renamed
(for example, to avoid capturing during substitution).
Please note: the renaming algorithm is likely be changed in the future,
no part of the system should rely on the particular algorithm.