[plt-scheme] Inspectors in mzscheme

From: Richard C. Cobbe (cobbe at ccs.neu.edu)
Date: Thu Jan 22 09:51:51 EST 2004

Lo, on Wednesday, January 21, Guillaume Marceau did write:

>   For list-related administrative tasks:
>   http://list.cs.brown.edu/mailman/listinfo/plt-scheme
> The following code does not behaves the same under drscheme and mzscheme
> with respect to inspectors:
>    (define-struct loc (x y) (make-inspector))
>    (display (format "~a~n" (make-loc 4 5)))
> Under mzscheme, it prints the opaque value:
>     #<struct:loc>
> Under drscheme, it prints the open value:
>     #(struct:loc 4 5)
> I'm not sure I understand why there is a difference.
> Is it possible to get the open value behavior under mzscheme?

Yes; simply set the value of the print-struct parameter to #t.  (I'm not
sure exactly what Robby's referring to; I got the same behavior that you
did with a CVS build from 16 Jan.)


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