Sun May 9 11:12:52 EDT 2010

I -> O -> C

About compileIO in DFL.hs - is it composable?

Is the following type I -> O -> C an arrow?  Here C is code.  This
type represents abstracted code where inputs and outputs can be filled
in.  I.e. linkable dataflow code.

The key question is : can this be made to compose?  Give two such
objects, can we turn it into one of similar type?

The problem is that we need some kind of composition operation on C.
I guess this could work, but since C is already defined from a more
general type (either opaque functions or concrete syntax trees) it is
probably a lot easier to perform the composition at those levels.

The composition of C objects is about _structure_, not functionality.
I.e. what kind of looping strategy to use.  Such transformations
cannot be performed on the function space!

So, it probably makes more sense to perform this kind of composition
on functions that map [n] -> [n].