The syntax of macro paths and processes is similar to the syntax of paths and processes of basic COSY:
We have used msequence instead of bsequence to stand for ``macro sequence'' since it may contain replicators and distributors as constituents. Similarly, in the syntax rules below, morelement will stand for ``macro orelement'':
In the above rules, gelement stands for ``generalized element'' since it can be any of mstarelement, sreplicator or distributor, possibly preceded by right replicators or succeded by left replicators, respectively. We have used sreplicator to indicate another kind of replicator which expands to basic COSY sequences, and which we call sequence replicators. The difference between the above rules and corresponding ones in basic notation is that here we allow six new types of elements. These are, sequence replicators and distributors, produced by sreplicator and distributor respectively, which cannot be starred, right and left replicators, produced by rreplicator and lreplicator, respectively, and indexed events and event slices, produced by the second alternative of mevent.