Re: term diff

Proof of concept:
write terms to files using write_canonical style.
Insert line breaks after (
and before and after )
so that f(g(x),h(x,y)) =>
f(
g(
x
)
,
h(
x
,
y
)
)

Now use a file difference algorithm (such as 'diff') on the two files.
I have a file difference program somewhere (it's written in Pascal, and
I no longer have a Pascal compiler, which is why it's "somewhere") that
can handle moves as well as adds and deletes.