> (run 1 (q)
    (fresh (w1 w2 w3 x board)
      (wire-link 1 2 w1)
      (wire-link 2 4 w2)
      (wire-link 5 x w3)
      (== q (list w1 w2 w3))
      (connectedo 3 5 q)))
Exception: variable == is not bound
Type (debug) to enter the debugger.
> ==
#<procedure>