[coffeecup]

Hello,

I have some issues to understand how parts of the following code are working:

demo:
http://devfiles.myopera.com/articles/649/example2.html
source:
http://devfiles.myopera.com/articles/649/example2.js

this is the part I have issues with:

var func = tool[ev.type];
    if (func) {
      func(ev);
    }

I don't quite get the idea behind this How does it work/what does it to?

Any help is welcome, thanks in advance!