init do end
end
class B
-special A
+ super A
fun foo do 0.output
init do end
end
class C
-special B
+ super B
fun bar do 1.output
init do end
end
#alt4# a.foo
end
+if not (not a isa B or a == a) then
+ a.foo
+end
+
+if a isa B implies a == a then
+#alt7# a.foo
+end
+
+if not (a isa B implies a == a) then
+ a.foo
+end
+
assert a isa B
a.foo