traced

The free traced category, i.e. diagrams with swaps where outputs can feedback into inputs.

Summary

Diagram	A traced diagram is a monoidal diagram with Trace boxes.
Box	A traced box is a monoidal box in a traced diagram.
Trace	A trace is a diagram arg with an output wire fed back into an input.
Category	A traced category is a monoidal category with a method trace.
Functor	A cartesian functor is a monoidal functor that preserves traces.