[racket-dev] Removing Xexpr preference from Web Server

From: Robby Findler (robby at eecs.northwestern.edu)
Date: Tue Nov 30 09:58:45 EST 2010

On Tue, Nov 30, 2010 at 8:04 AM, Eli Barzilay <eli at barzilay.org> wrote:
> Two hours ago, Robby Findler wrote:
>> On Tue, Nov 30, 2010 at 5:18 AM, Eli Barzilay <eli at barzilay.org> wrote:
>> >
>> > The problem here is that there is no name to change -- it's the
>> > implicit "coercion" of xexpr values to a response.
>>
>> Why can't there be two libraries, one that coerces and one that
>> doesn't? More generally, one that acts the same as the current
>> library and one that is intended for new code?
>
> That would require a new `web-server' module, as well as a whole bunch
> of other modules.

I know.

> Even worse, writing a module using one web server
> library, and using it in the other won't work, since it's a dynamic
> property of how the result is getting used.

(I think it may be possible to be creative to avoid these things being
errors when you mix; but maybe it is better to have an error when you
mix; I don't have a strong opinion here but I'd try to make mixing
work so people can migrate piecemeal.)

---

As I said before, we have done this with the class system many times.
We have done this with other parts of the system as well (not as many
times tho). It is not a simple thing.

That said, massive backwards incompatibility as Jay is proposing seems wrong.

Robby


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