[racket] cool things in Whalesong, part 2

On Mon, Mar 5, 2012 at 5:32 PM, Jens Axel Søgaard <jensaxel at soegaard.net> wrote:
> I'll give it a spin tomorrow.


Heads up for folks who are using the development version of Whalesong
off of my github repo:  I've revised the design for how we introduce
new world event handlers.  It's incompatible with the previous
proposal, unfortunately, but it fixes a major flaw.

The prior proposal incorrectly missed out on the need to turn off the
event handling once a big-bang finishes.

The use of it now looks more like this:

    https://github.com/dyoo/whalesong/blob/master/js/world/geo.rkt

Creating a new world handler type involves the function
"make-world-event-handler".
When we use it, we pass it both setup and shutdown procedures.  The
setup gets to return a value that the shutdown can use to do cleanup.