fact: Definition switch {N : monad} (p t : door) : N door := Ret (head def (doors \\ [:: p ; t])).
imports: Reals Lra mathcomp(all_ssreflect ssralg ssrnum) mathcomp(mathcomp_extra reals Rstruct) infotheo(ssrR realType_ext Reals_ext proba) monae_lib hierarchy monad_lib fail_lib proba_lib