segment(p,q)
i1 : p=point(2.1, 3.,4.) o1 = Point3D{2, 3, 4} o1 : Point3D
i2 : q=point(.4, 4.6,5.3) o2 = Point3D{0, 5, 5} o2 : Point3D
i3 : segment(p,q) o3 = Segment3D{Point3D{2, 3, 4}, Point3D{0, 5, 5}} o3 : Segment3D