intuition.
simpl.
eapply comp_spec_eq_refl.
Qed.

Theorem compFold_support_h :
forall (A B : Set)(eqda : EqDec A)(P : A -> list B -> list B -> Prop)(c : A -> B -> Comp A) (ls1 ls2 ls3 : list B)(a z : A),
In z (getSupport (compFold _ c a ls1)) ->
P a ls2 (ls1 ++ ls3) ->
(forall a1 a2 b ls1 ls2,
In a2 (getSupport (c a1 b)) ->
P a1 ls1 (b :: ls2) ->
P a2 (ls1 ++ (b :: nil)) ls2
) ->
P z (ls2 ++ ls1) ls3.