[plt-scheme] Re: Restart Web-server

From: YC (yinso.chen at gmail.com)
Date: Sat Nov 7 13:22:11 EST 2009

On Thu, Nov 5, 2009 at 12:24 AM, Japus <jasper.maes at gmail.com> wrote:

> I already tried the meta-refresh technique and javascript too but the
> problem with those is that when I use a variable in it, it reads it's
> value when the code is generated and based on that it decides how long
> it takes to reload but it should reload when the value of that
> variable changes.


Jasper -

Meta-refresh gets you half way there with almost no work, but the remaining
half way is a major undertaking if you haven't done it before, so that's why
I mentioned meta-refresh as an option unless you are ready to go all the
way.

Assuming you are ready to go all the way - you'll have to get familiarized
with ajax & http comet, as they are the solution to your question.  There
are abundant information on these topics on the web and books.  The
techniques are server independent, so you can use them with plt web-server.

>
> So it should constantly check the variable and see
> if the variable has changed and when it has, instantly reload. If it
> hasn't changed, nothing should happen.
>

The $64K question here is: since the variable exists on the server, and you
need to "constantly" check it from the client, how do you do so without a
"reload"?

Again - look at ajax & comet - they are designed specifically to answer this
question.

HTH.  Cheers.
yc
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.racket-lang.org/users/archive/attachments/20091107/7693fbfb/attachment.html>

Posted on the users mailing list.