Goal:
    A : Type  P : list A → list A → A → A → Type  H : True
  ============================
   ({| pr1 := {| pr1 := []; pr2 := [] |}; pr2 := All2_fold_nil P |} =
    {| pr1 := {| pr1 := []; pr2 := [] |}; pr2 := All2_fold_nil P |})


DEBUG:Going to execute:
destruct id
DEBUG LTAC Evaluated term: H
DEBUG LTAC Evaluated term: True
Level 6: type of H
 has value 
True

Level 6: Backtrace:

No matching clauses for match.
Level 5: Backtrace:

No matching clauses for match.
Level 5: evaluation
raised the exception
Backtrace:

No matching clauses for match.

Level 5: Backtrace:

No matching clauses for match.
Level 4: Backtrace:

No matching clauses for match.