Well yes, I deliberately overstated this but.
Stavros Macrakis wrote:
> .....
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>What a DTD/Schema allows you to do is to specify restrictions on
>structures, so as to disallow -- at read time -- things like
>
> (mplus x (((x) 1) 3))
>
This is true, but there are lots of things that you would have trouble
specifying as
illegal, even though they are illegal.
Consider this
((mplus) ((f ) x) ((f) x y)).
Why is this illegal? either f has one argument or two.
Is this always illegal? Actually no, you COULD define f in some
way to take more than one argument, but maybe you haven't.
It may also be the case that the strange object above... (mplus x (((
.......
COULD be used in macsyma, since macsyma can call lisp...
[admittedly arguing for the sake of argument...]
RJF
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