fact: Definition part_update fp (i : subpart_loc) := forall (r : prange) p, size_part (fp r p) = (size_part p).+1 /\ (forall G x, @fitp G x (fp r p) -> r (arity (i G x)) /\ (forall r' : prange, r' (arity (i G x)) -> fitp x (fp r' p))).
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap color geometry)