fact: Fixpoint InA (l:seq A) (a:A) : bool := match l with | [::] => false | x :: xs => if eqA_dec a x then true else InA xs a end.
imports: Coq(RelationClasses Setoid Morphisms SetoidList Mergesort Permutation) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq fintype) mathcomp(bigop path) RegexpBrzozowski(glue)