Changed from call to make-callable and extend-morphism
wrote xi, maybe it works?
I think everything including xi works
Accurate 0-diagonal for [0,1]
Accurate 0,1-diagonal for [0,1], must tidy up
Added a tidy function, things seem to work
I have to make tidy work without cutting corners, but then I should be in good form
working memoization
memoization works, fixed typo in comment