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Re: type specifiers for local variables

At 05:24 AM 3/12/99 -0800, Robert D. Skeels wrote:
>Just as an informational aside, the original Dylan language had to deal
>with this issue since it was based strongly on Scheme's syntax. Although
>its object system is much like CLOS, the designers seemed to stick more to
>the Scheme spirit than that of CL. They used the extra parentheses as in
>Per's first example.

I would be just as happy to align these extensions with Dylan rather than
CL, and it is clrearly a more compatible direction - particularly if Kawa
could wind up being fully compatible with Dylan.  Considering that there
are Dylan implementations in Scheme, it should probably be very easy to add
the missing pieces.

I do want to say though that it seems the Dylan designers have made an
error in this bind/let form since:

     (bind ((x <integer>)))

Is ambiguous if types/classes are first class objects because it is then
indistinguishable whether x is declared type integer but not initialized or
whether x is of object type and initialized to the integer type object.
But I don't have the Dylan docs so I don't know whether there is some other
expression that gives a type as a value, so perhaps this is not an problem.

It is difficult to find information about Dylan on the web, but I did find

An interesting thing about the points made there is that the features which
are un-Scheme-like are exactly those which are (or have been)
un-Scheme-like in Kawa.

Perhaps Kawa should just switch to being Dylan for the Java VM (perhaps
with a few extensions for greater Schemeishness as they become available).

Ahh, found the docs:

But now I'm really confused.  The Thomas stuff has LISP syntax but this doc
shows an Algolish thing, which reminds me why I wasn't interested in Dylan
when I first saw it.

Well, this hook up with Dylan still makes some sense.  If Kawa were to
adopt the Thomas style, then it will be easy and quite cool for someone to
add the Dylan parser.

James P. White                 Netscape DevEdge Champion for IFC 
IFC Exchange   *   Insanely great Java   * Pagesmiths' home is