Python can easily extend applications that offer it, and will allow your to do some interesting things not only with workflow, but also in creating project specific tools. here, Pim Grooff shows 3 different ways to use Python within Cinema 4D to calculate or return the length of a spline.
Short tutorial using 3 ways to calculate the length of a spline
Pim shows that this can be done by using the distance between node and getting the first and last point of the spline, or by using the SplineLength Data class, or by using the bounding box method. Pim also discusses the benefits and drawbacks for using each to recover the length of a spline.