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

From: Norbert Lehmann (Norbert.Lehmann at unifr.ch)
Date: Fri Jul 25 08:11:59 EDT 2003


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)


Thanks very much

                                (o o)
Norbert Lehmann
Department of Informatics (DIUF)            phone: ++ 41 26 300 83 30
University of Fribourg                        fax: ++ 41 26 300 97 26
Rue Faucigny 2                       e-mail: Norbert.Lehmann at unifr.ch
CH-1700 Fribourg                    http://www-iiuf.unifr.ch/~lehmann
                              (_)   (_)

Posted on the users mailing list.