func a x .
   print "->a: " & x
   return x
.
func b x .
   print "->b: " & x
   return x
.
print "1 and 1"
if a 1 = 1 and b 1 = 1
   print "-> true"
.
print ""
print "1 or 1"
if a 1 = 1 or b 1 = 1
   print "-> true"
.
print ""
print "0 and 1"
if a 0 = 1 and b 1 = 1
   print "-> true"
.
print ""
print "0 or 1"
if a 0 = 1 or b 1 = 1
   print "-> true"
.
