[plt-scheme] typed scheme vs. PLAI types

On Mon, Feb 8, 2010 at 8:03 PM, keydana at gmx.de <keydana at gmx.de> wrote:
> This looks rather ugly, especially having structs for the Is, And and Or expressions... I guess this should  be done completely differently, but I don't see how. (So my first question would be, how can I do this better in typed scheme?)

Not as far as I know -- unless you use a macro. Here's one Dave Herman
wrote earlier:

http://planet.plt-scheme.org/package-source/dherman/types.plt/2/0/planet-docs/types/index.html

>
> My second question is, why does typed scheme not have such a define-type? (I find it very appealing because it makes the algebraic type definition very concise.)

Dunno. I reckon it should.

N.