top-level instances: 
Instances:
  I = inv<> I
  J = inv<> J
  a = bool<> a
  b = bool<> b
  c = bool<> c
a (type: bool<>) has members: 
I (type: inv<>) has members: 
Instances:
  a = bool
  b = bool
J (type: inv<>) has members: 
Instances:
  a = bool
  b = bool
I.a (type: bool<>) has members: 
