In this talk, I sum up some aspects of code design that has been floating around since the early 1990s but have failed to materialize in the CLASSIC/MAD9 debacle. In particular, I examine two things: 1) a polymorphic type for the ray leading to the computation of virtually anything in perturbative theory. 2) the beam line viewed as a doubly-linked link list where each element is actually the discretized position along the ring. Hanging off the chain links are elements of the Euclidean groups as well as magnets or pointers to magnets. Each magnet contains a single particle propagator (and a reverse propagator). I have applied these structures to recirculators and a pretzel type double ring.


Talk Slides: PDF