proposition: Theorem gsspec {A} i j x (m: t A) : find i (add j x m) = if E.eq_dec i j then Some x else find i m.
proof: Proof. destruct (E.eq_dec i j) as [->|]; [ apply add_spec1 | apply add_spec2; auto ]. Qed.
imports: Coq(Bool PeanoNat BinPos Orders OrdersEx OrdersLists) MMaps(Utils Comparisons Interface)