mod! EXPERIMENT {
  pr(ABP)
  [Observation < StateSpace]
  op __ : StateSpace StateSpace -> StateSpace {assoc comm}
  op hs2es : Sys -> StateSpace
  op fifo1:_ : PFifo -> Observation
  op fifo2:_ : BFifo -> Observation
  op bit1:_  : Bool -> Observation
  op bit2:_  : Bool -> Observation
  op next:_  : Nat -> Observation
  op list:_  : List -> Observation
  var S : Sys
  eq hs2es(S) = (fifo1: fifo1(S)) (fifo2: fifo2(S)) 
                (bit1: bit1(S)) (bit2: bit2(S)) 
                (next: next(S)) (list: list(S)) .
}

eof

open EXPERIMENT
  ops s0 s1 s2 s3 : -> Sys .
--> init
  red hs2es(init) .
-->  s1 = rec2(dup1(drop1(send1(send2(send1(init)))))) .
  eq s1 = rec2(dup1(drop1(send1(send2(send1(init)))))) .
  red hs2es(s1) .
--> s2 = rec1(rec1(send2(s1)))
  eq s2 = rec1(rec1(send2(s1))) .
  red hs2es(s2) .
--> s3 = rec2(rec2(rec2(dup1(send1(s2)))))
  eq s3 = rec2(rec2(rec2(dup1(send1(s2))))) .
  red hs2es(s3) .
close