Goal:
    a : byte  b : byte
  ============================
   (forall e : NoConfusion_byte a b,
    noConfusion_byte_obligation_2 a b (noConfusion_byte_obligation_1 a b e) =
    e)


DEBUG:Going to execute:
let H := fresh x in
           intro
           H
Level 2: Backtrace:

The first hypothesis in the goal is not an equality.
Level 2: Backtrace:

The first hypothesis in the goal is not an equality.
Level 2: Backtrace:

The first hypothesis in the goal is not an equality.
Level 2: Backtrace:

The first hypothesis in the goal is not an equality.