fact: Definition nt_par u v := match u,v with | nt_test a, nt_test b => nt_test [elem_of a·elem_of b] | nt_test a, nt_conn b u c => nt_test [elem_of a ∥ elem_of b·u·elem_of c] | nt_conn a u b, nt_test c => nt_test [elem_of c ∥ elem_of a·u·elem_of b] | nt_conn a u b, nt_conn c v d => nt_conn [elem_of a·elem_of c] (u ∥ v) [elem_of b·elem_of d] end.
imports: HB(structures) Coq(Setoid Morphisms) mathcomp(all_ssreflect) GraphTheory(edone preliminaries setoid_bigop structures)