[plt-scheme] Type scheme annotations and macros

Oh, right. Duh.

On Wed, Oct 22, 2008 at 10:53 AM, David Van Horn <dvanhorn at ccs.neu.edu> wrote:
> Robby Findler wrote:
>>
>> What about
>>
>> (bif e1 e2 e3) => (if (and e1 #t) e2 e3)
>
> But this doesn't force e1 to have type Boolean.
>
> #lang typed-scheme
> (if (and "Not a Boolean" #t)
>    'a
>    'b)
>
> I want a form of if which will reject the following:
>
> (if "Not a Boolean"
>    'a
>    'b)
>
> David
>
>