[plt-scheme] ...does not implement #<struct:|interface:host<%>|>

The scheme:text mixin needs it's argument to implement the mode:host-text<%>
interface (sorry, the names get shortened in the error messages). 

You might be better off mixing the return mixin onto the scheme:text%
class. 

Check out the documentation for the details on the new classes.

Robby

At Fri, 25 Jul 2003 14:11:59 +0200, Norbert Lehmann wrote:
>   For list-related administrative tasks:
>   http://list.cs.brown.edu/mailman/listinfo/plt-scheme
> 
> Hello
> 
> The program below (which is part of a larger program) works fine on
> my Macintosh with DrScheme, Version 204. However, when I try to execute
> it with DrScheme, Version 204.8-cvs17jul2003 german, I obtain the
> following error message:
> 
> --------------------------------
> text-mixin: argument #<struct:class:transcript:return%> does not implement 
> #<struct:|interface:host<%>|>
> --------------------------------
> 
> What is the problem? Here is the program:
> 
> --------------------------------
> (module main mzscheme
>   (require (lib "framework.ss" "framework"))
>   (require (lib "mred.ss" "mred") (lib "class.ss"))
> 
> (define transcript:return%
>   (class text:return% (init (return driver-loop))
>     (super-instantiate () (return return))))
> 
> (define transcript:editor% (scheme:text-mixin transcript:return%))
> 
> (define (driver-loop)
>   #t)
> 
> )
> --------------------------------
> 
> Thanks very much
> Norbert
> 
> -- 
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