Deep-equal between sequences

[Ronald Bourret]

Michael Kay wrote:
> The downside is that the semantics of deep-equal are themselves so fragile -
> the function so often doesn't perform exactly the comparison you would like.

Which is my case -- I don't actually need deep-equal, but something 
close to it. It was just the easiest way to explain the problem.

> Another solution you could try to implement at application level would be to
> define a hash function such that deep-equal(A, B) => hash(A) eq hash(B), and
> then confine the deep-equal() comparisons to nodes where the hash values are
> equal. A good start might be hash($N) == string($N). Not very effective
> where most of the information is held in attributes, but OK in most other
> cases.

Another good idea.

-- Ron