[~] /users/btools/IBEN/bin/iben
Interactive BDD Environment version 1.0
of Dec  4 1998 01:12:00 compiled with GCC 2.8.1
Copyright (c) 1998, Aalborg University
iben> vars x y z
iben> f := (x & y) | z
iben> print f
<0/0:0, 2/2:1><0/0:1, 1/1:0, 2/2:1><0/0:1, 1/1:1>
iben> satisfy f
!x z 
iben> g := exists x (forall z (z | (x & y) ))
iben> vars w
iben> h := subst [w/y] (g)
iben> print h
<3/3:1>
iben> satisfy h
w 
iben> show h
iben> executing ghostview
Warning: Cannot convert string "-dt-interface user-medium-r-normal-s*-*-*-*-*-*-*-*-*" to type FontStruct
iben> quit
[~]