[racket] typed racket and interfaces

On May 1, 2014, at 11:49 PM, Asumu Takikawa <asumu at ccs.neu.edu> wrote:

> On 2014-05-01 22:53:49 -0400, Alexander D. Knauth wrote:
>> Is there a way to specify inheritance in a class or interface type
>> constructor (so then you can avoid some copying and pasting)?
> 
> IIUC, your question is basically "why does #:implements in Class types
> not copy over initialization arguments?”.
I didn’t know about #:implements, and when I tried to use it, it gave me an error telling me that #:implements wasn’t a valid type, and the docs don’t say anything about it.  Is #:implements only in a later version (I have 6.0), or does it need to be used in a certain place, or what?