fact: Definition ecp_eq u v := match u, v with | IcpX, IcpX | IcpXe, IcpXe => true | Icp x, Icp y => x == y :> A | _, _ => false end.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap geometry color)