union, however, it does not place the point of interest into line B in the correct sequence (at index 1, assuming the start point of B has index 0, and the end point of B has index 2). Diagram shown above ^^^
linearrefclasses. E.g. one thing you could do is to compute the index of the endpoint of A along line B. Then perhaps extract the two sublines of B from the start to the point, and the point to the end, and then
IndexedLineclasses which will add a vertex at a given index.