Section alistFacts.
(* Generic facts about alists. To eventually move to ExtLib. *)
Arguments alist_find {_ _ _ _}.
Definition alist_In {K R RD V} k m v := @alist_find K R RD V k m = Some v.
Arguments alist_add {_ _ _ _}.
Arguments alist_find {_ _ _ _}.
Arguments alist_remove {_ _ _ _}.
Context {K V: Type}.
Context {RR : @RelDec K (@eq K)}.
Context {RRC : @RelDec_Correct K (@eq K) RR}.

Lemma alist_find_add_none:
forall m (k r :K) (v:V),
alist_find k (alist_add r v m) = None ->
alist_find k m = None.