theorem :: GLIB_006:110

for G2 being _Graph
for v1, v2 being Vertex of G2
for e being object
for G1 being addEdge of G2,v1,e,v2 st not e in the_Edges_of G2 holds
( G1 .order() = G2 .order() & G1 .size() = (G2 .size()) +` 1 )