[Aldor-l] implementing aldor / new species approach

[root]

> It would be OK for me though to implement only a part of the Aldor
> language. In fact, SPAD implements a subset of the Aldor language,
> at least roughly. It has proven to be quite useful, you can even
> implement a computer algebra system with it. Only, meanwhile we hit
> the restrictions on dependent types and types being first class
> objects (I.e., List Ring is not allowed), so it is time to extend
> it. I wouldn't though it away, unless it turns out that this is
> easier. I'd be very happy with the old SPAD compiler, if it would
> understand dependent types, at least in the most common cases. And I
> want to be able to say l: List Ring := [Integer, Polynomial Integer,
> PF 5].

Ring is implemented as a lisp object. You can put these into a list.

There is no inherent restriction on creating lists of domains
except for the spad compiler, which can be changed.

t