Formatting tests, mainly for readability
Make dedicated stream dimension object
extend dimension calculation to nested patches.
Force reading patches to be wrapped in (% ...)

You have to wrap a patch meant to be composed with an existing
sub-patch of input to distinguish it from a subpatch merely
meant to be inserted.
Complete rewrite of compose to support first nested composition.

Yes.
Another test case

Need to figure out how to generate reading patches. And write docs.
Another test case for nesting
Correct return type on compositions that return empty patch
One more test case
Get rid of patch constructor.
refactor compose-single for, um, clarity

unconditionally extract the inside from the lhs reader
and do the testing on that inside, rather than using predicates
on the reader itself that will just do the same thing inside
heavily edit readme to reflect nesting, still pretty rough
move (defn patch? ...) closer to usage
Allow lists to be patches too.

compose actually returns a list because of the use of cons,
so the results of compose for subpatches still need to be
recognized as patches even though they're not vectors, as
previously expected.