                         return v.z
                     default:
                         assert(false, "nope!")
+                        return 0.0 // TODO: fix
                 }
             }
             var p: [BKFloat] = self.dpoints[0].map(mfn)

        }
        else {
            assert(false, "what?")
        }
    }
    

        }
        else {
            assert(false, "what?")
            return SplitResult.singleCurve(curve: self) // TODO: fix
        }
    }

