fact: CoInductive supp_spec x (s : fmap) : bool -> Type := | supp_spec_some v of fnd x s = Some v : supp_spec x s true | supp_spec_none of fnd x s = None : supp_spec x s false.
imports: mathcomp(ssreflect ssrbool eqtype ssrfun seq path) LemmaOverloading(ordtype prelude)