On Tue, 27 May 2003, Aaron J Reichow wrote:

> However, I've been working on something like this for Dynapad.  The only
> support an object has to have to use this well is a method which returns
> an array of symbol for the names of the variables which are to be
> modified, along with the type.  That is, for a simple addressbook:
>
> ^ #( (#name #String) (#age #SmalInteger) (#birthday #Date))
>
> meaning, you can enter any string in the name box, any number in the age,
> and you get a date picker for birthday.

Of course, do you really want to be able to put *any* number in the age?
More likely you want this to be between 0 and, oh, 120 or so. Similary,
what do you do with (#zipCode #SmallInteger)?  What about collections?
Would you just do (#children #Set), or (#children #Set #Person), or what?

I bring this up not because I think you need to address these right away,
but because I think building UIs based on this kind of metadata is a
useful thing to explore, and I would love to see a well done standard way
of expressing these things.