On Sat, Nov 23, 2013 at 11:57 PM, H. S. Teoh <hsteoh@quickfur.ath.cx> wrote:
> void delegate(Event) dg = (Event e) {
>                 if (e == ...)
>                         queue.remove(dg); // NG: Still complains 'dg' isn't defined
>         };
>         queue.register(dg);

Did you try this?

void delegate(Event) dg;

dg = (Event e) {
    if (e == ...)
        queue.remove(dg); // NG: Still complains 'dg' isn't defined
};

queue.register(dg);

On Sun, Nov 24, 2013 at 12:24:53AM +0100, Philippe Sigaud wrote:
> On Sat, Nov 23, 2013 at 11:57 PM, H. S. Teoh <hsteoh@quickfur.ath.cx> wrote:
> > void delegate(Event) dg = (Event e) {
> >                 if (e == ...)
> >                         queue.remove(dg); // NG: Still complains 'dg' isn't defined
> >         };
> >         queue.register(dg);
> 
> Did you try this?
> 
> void delegate(Event) dg;
> 
> dg = (Event e) {
>     if (e == ...)
>         queue.remove(dg); // NG: Still complains 'dg' isn't defined
> };
> 
> queue.register(dg);

You're right, separating the dg declaration from the body of the delegate fixes the problem.

But still, it's rather ugly. I wish there were a way for a delegate to refer to itself.


T

-- 
Frank disagreement binds closer than feigned agreement.

On Sun, Nov 24, 2013 at 12:15:23AM +0100, lomereiter wrote:
> Why so much fuss about delegates? I would simply define an interface.
[...]

I know I can do that (and in fact it's what I had before).

But classes and interfaces are rather heavy (more indirection, allocates vtables, etc.), and require the declaration of tiny classes everywhere, which is a pain when I have many tiny code snippets I wish to register and unregister in various places. Using delegates is much cleaner (thanks to lambda syntax) and lighter weight, especially when I need to close over local variables.


T

-- 
May you live all the days of your life. -- Jonathan Swift