Event handling

[Bill Baxter]

Frank Benoit wrote:
> Bjoern schrieb:
>> Is such a hack really nessesary ? ( ... Sorry ... )
>>
>> I mean A look at old school Smalltalk's  message handling should teach 
>> us that "code blocks" // in our D case : closures // enable us to find a
>> smarter solution. So I vote for spending  a reasonable amount of time 
>> to figure out either a good/better D-ish solution or give a smalltalk 
>> like solution a try.
>>
>> Just my unholy opinion / the current DWT event handling is a bit clumbsy.
>> ->
>> Well, Closures are a D2 feature . and implementing code blocks using 
>> closures is not very smart .. THough I'm  conviced that a closure 
>> based solution is worth thinking twice...
>>
>> OT ---------------------------------------
>> D blocks : Pseudo code
>> ------------------------------------------
>> for_each = function (list, block)
>> {
>> for (i = 0; i < list.sizeof(); ++i)
>> block(list[i])
>> }
>>
>> list = #(12, 34, 56) // tuple
>> for_each(list)
>> { |x| Print(x) }
>>
>> =>  12
>> 34
>> 56
> 
> I don't get what your example shall illustrate.
> Can you explain a bit more verbose?

Bjoern, I don't really get what you're saying either, but it sounds 
vaguely like you're saying let's make delegates be usable as event handlers.

That's basically what this adapter template does.  It lets you say :

   setListener(dgWrapper(
      (Event ev) { Print(ev); }
   ));

Instead of:

   setListener(new class Listener {
      void handleEvent(Event ev) {
         Print(ev);
      }
   });

The next step would be to add an override to the setListener method to 
take a delegate and create the _DgListenerWrapperT automatically under 
the hood.  Then you could do:
   setListener(
     (Event ev) { Print(ev); }
   )

but that wouldn't allow passing the extra args.

--bb