Goal:
    A : Type  P : list A → A → Type  x : A  a : All_fold P [x]
  ============================
   (P [] x)


DEBUG:Going to execute:
t; easy
Level 3: evaluation returns
DepElim.do_depelim_nosimpl tac H; DepElim.simpl_dep_elim;
 CoreTactics.unblock_goal
where
tac := fun hyp => DepElim.do_case hyp
       where
       id := a
       of type
       ident
of type
tacvalue
H := a
of type
ident of type tacvalue

Level 2: evaluation returns
DepElim.do_depelim_nosimpl tac H; DepElim.simpl_dep_elim;
 CoreTactics.unblock_goal
where
tac := fun hyp => DepElim.do_case hyp
       where
       id := a
       of type
       ident
of type
tacvalue
H := a
of type
ident of type tacvalue

Level 1: evaluation returns
DepElim.do_depelim_nosimpl tac H; DepElim.simpl_dep_elim;
 CoreTactics.unblock_goal
where
tac := fun hyp => DepElim.do_case hyp
       where
       id := a
       of type
       ident
of type
tacvalue
H := a
of type
ident of type tacvalue