[plt-scheme] Problems with class definition

You want:

  (send m rows)

rather than

  (send rows m)

Robby

At Thu, 14 Nov 2002 23:12:36 +0100, Harald Schmidt wrote:
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> 
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> I would like to define a matrix class, the syntax check is okay, but the
> object doesn't understand the rows method. Could anyone tell me
> what's wrong with the definition.
> 
> Harald
> 
> (define matrix<%> (interface () rows))
> 
> (define matrix%
>    (class* object% (matrix<%>)
> 
>      (init-field (rows-size 0) (cols-size 0))
> 
>      (define/public rows
>        (case-lambda
>          ((new-rows-size) (set! rows-size new-rows-size))
>          (() (rows-size))))
> 
>      (super-instantiate ())))
> 
> (define m (instantiate matrix% ()))
> (send rows m)
> 
> Welcome to DrScheme, version 202.
> Language: Pretty Big (includes MrEd and Advanced) custom.
> reference to undefined identifier: rows
>  > 
> 
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