fact: Definition Frag (p: DF * DC) := (sval (FD.(fd_trees) (ssvalP p.1) (ssvalP p.2))).
imports: mathcomp.ssreflect.ssreflect mathcomp(all_ssreflect) CompDecModal.libs(edone bcase fset base sltype) CompDecModal.CTL(CTL_def dags)