RE: Spad and inductive types

On Tue, 8 May 2007, Bill Page wrote:

| > I have more to say later.
| 
| We're listening. :-)

One of the issues I have with many of the various alternatives is
that they make definition of new functions operating on Expr
also impossible (by a third person) without intimate knowledge
of the representation of Expr, or modifying the Expr domain.

In contrast, in Haskell or Boot codes, once I give that data type
definition, people are free to add more operations without knowing
more of the internal representations.  

That is not quibbling.

-- Gaby