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Re: Dylan Constants

>      From the Dylan reference, there appears to be now way of defining a read
>     only constant ala the Common Lisp DEFCONSTANT macro. 

One thing, I don't like in the CL DEFCONSTANT spec is that it mixes
the concepts of bindings and data structures. 
In an object oriented language like Dylan it should be a property of
the anonymous object if it is read only or not. The question if the
binding is mutable or immutable is an orthogonal one, although the
compiler can make more optimizations if both the binding and the
object are read only.

> The Dylan people at Apple have indicated that this will be fixed.  I don't
> know if they've yet settled on a choice of syntax, but I believe the
> current plan is that *all* the "define" forms will produce constants, and
> some new form will be created for defining non-constant variables.

In EuLisp, we adopted the same approach.


Harry Bretthauer
German National Research Center for Computer Science (GMD)
P.O. Box 1316, W-5205 Sankt Augustin 1, Germany
Phone: +49-2241-14-2704   Fax: +49-2241-14-2072 Email: bretthauer@gmd.de