[plt-scheme] typed scheme vs. PLAI types

From: keydana at gmx.de (keydana at gmx.de)
Date: Tue Feb 9 16:17:26 EST 2010

Hi Noel,

thanks a lot for the hint! I will use it then, till typed scheme will have something similar.
One question: how do I pattern match against the various data constructors?

Many thanks

Am 08.02.2010 um 21:28 schrieb Noel Welsh:

> 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.

Posted on the users mailing list.