A feture adjustment request and a syntax blasphemy

BCS nobody at pathlink.com
Sun Oct 29 20:54:36 PST 2006


Closures and currying provide some of what I was looking for. However, if I
understand them correctly*, they don't do exactly what I want.

The closure approach would be fine if it didn't require some language magic or
annotations to get the local parameters off the stack. The system I used avoids
this by dynamically allocating off the heap for the context. (this is only better
than annotation because it doesnít require language support)

Currying (again, if I understand correctly) will end up using some sort of runtime
generated function or a wrapper delegate that manipulates the stack (another form
of a closure) again this doesnít quite have the effect I'm looking for. In this
case it is because of the extra call/return overhead.

Really what I want is to be able to form a delegate from any heap item and a
literal code block. particularly I want the context of such a thing to be the heap
item, not the enclosing scope.

<ptr_type>.delegate <type>(<type_list>){<code>}

FWIW, I got the program I posted working but had to use an anonymous class with
the function as a method. Not as clean a solution because of the overhead
involving objects, but it works.

{
	auto c = new class{
		T delegate() d;
		T action()
		{
			return d();
		}
	}
	return &a.action;
}

*I havenít read the article DavidM cited yet (lack of time n'all)


== Quote from Jarrett Billingsley (kb3ctd2 at yahoo.com)'s article
> "BCS" <BCS at pathlink.com> wrote in message
> > So why no this?
> >
> >   static int[] i = [1,2,3];
> >   i.function void(int[] j){return;}();
> How about:
>  static int[] i = [1,2,3];
>  auto f = function void(int[] j){return;};
>  i.f();
> ?


I was trying to get away without the temporary. If you will notice, you suggestion
is effectively the same as the example of something that works that I gave.



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