proposition: Lemma tcast_val (T: Type) m n (H: m = n) (l: m.-tuple T): tval (tcast H l) = tval l.
proof: Proof. by case: n / H. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq choice fintype order bigop ssralg) mathcomp(div ssrnum ssrint rat prime path binomial) mathcomp(tuple finset) gaia(fibm)