  --> [ local path prefix ]/top_ports/unmatched_types.fpp:32:5
   |
32 |     A.a -> A.b
   |     ^^^ cannot connect port types P1 and P2
   |
  ::: [ local path prefix ]/top_ports/unmatched_types.fpp:23:3
   |
23 |   port a = c1.pOut
   |   ---------------- from port is specified here
   |
  ::: [ local path prefix ]/top_ports/unmatched_types.fpp:24:3
   |
24 |   port b = c2.pIn
   |   --------------- to port is specified here

