http://www.hans-eric.com/2007/09/11/d-doesnt-have-real-closures/

Please digg and reddit.

BA

Brad Anderson wrote:
> http://www.hans-eric.com/2007/09/11/d-doesnt-have-real-closures/
> 
> Please digg and reddit.
> 
> BA

You want multicast?

Well, for multicast functions (with one parameter) it seems to be
rather straightforward template programming:

---<snip>---
module multicastFunctions;

template mcf(T)
{
  class mcf
  {
    void function(T) fun;
    mcf next;

    void opCall(T x)
    {
      fun(x);
      if (next !is null)
        next(x);
    }

    mcf opCat(mcf n)
    {
      mcf m=this.dup();
      m.next=n.dup();
      return m;
    }

    mcf dup()
    {
      return new mcf(this);
    }

    this(mcf m)
    {
      this(m.fun,m.next);
    }

    this(void function(T) d,mcf n=null)
    {
      fun=d;
      next=n;
    }
  }
}

void fa(int x)
{
  printf("fa(%i)\n",x);
}

void fb(int x)
{
  printf("fb(%i)\n",x);
}

void main()
{
  mcf!(int) a=new mcf!(int)(&fa);
  mcf!(int) b=new mcf!(int)(&fb);
  mcf!(int) c=a~b;
  a(1);
  b(2);
  c(3);
}
---<snap>---

I am sure with all the templating wizzards floating around here
someone can come up with something that is not quite as full of
crap as my little proof of concept code, probably with multiple
parameter feature and whatnot; dirty and obvious hack for multi
parm would be to have N copies of the template for 0..N-1 parms.

Look ma, no C#!

Regards, Frank

"0ffh" <spam@frankhirsch.net> wrote in message news:fc6mea$4d8$1@digitalmars.com...
> Brad Anderson wrote:
> I am sure with all the templating wizzards floating around here
> someone can come up with something that is not quite as full of
> crap as my little proof of concept code, probably with multiple
> parameter feature and whatnot; dirty and obvious hack for multi
> parm would be to have N copies of the template for 0..N-1 parms.

Oh please, D has variadic templates :D  That, and I'd expect something like this to be a value type.

struct MCD(Args...)
{
    void function(Args)[] funcs;

    void opCatAssign(void function(Args) f)
    {
        funcs ~= f;
    }

    void opCall(Args args)
    {
        foreach(f; funcs)
            f(args);
    }
}

void fa(int x)
{
    Stdout.formatln("fa({})", x);
}

void fb(int x)
{
    Stdout.formatln("fb({})", x);
}

void main()
{
    MCD!(int) a;
    a ~= &fa;
    a ~= &fb;
    a(3);
}

Brad Anderson wrote:
> http://www.hans-eric.com/2007/09/11/d-doesnt-have-real-closures/
> 
> Please digg and reddit.
> 
> BA

Reddit:

http://programming.reddit.com/info/2o4we/comments

Digg:

http://www.digg.com/programming/D_doesn_t_have_real_closures

Jarrett Billingsley wrote:
>> Brad Anderson wrote:
>> I am sure with all the templating wizzards floating around here
>> someone can come up with something that is not quite as full of
>> crap as my little proof of concept code, probably with multiple
>> parameter feature and whatnot; dirty and obvious hack for multi
>> parm would be to have N copies of the template for 0..N-1 parms.
> 
> Oh please, D has variadic templates :D  That, and I'd expect something like this to be a value type.

It is quoted a bit like I wrote this blog post, but I did not.  I'm just the marketing guy here.

BA

Brad Anderson wrote:
> It is quoted a bit like I wrote this blog post, but I did not.  I'm just
> the marketing guy here.

Ups, sorry, my mistake!

Regards, Frank

"Brad Anderson" <brad@dsource.org> wrote in message news:fc7kh6$1jin$1@digitalmars.com...

> Jarrett Billingsley wrote:
>>> Brad Anderson wrote:
>>> I am sure with all the templating wizzards floating around here
>
> It is quoted a bit like I wrote this blog post, but I did not.  I'm just the marketing guy here.

Oops, misquote there.  Should've been 0ffh.

Brad Anderson wrote:
> http://www.hans-eric.com/2007/09/11/d-doesnt-have-real-closures/

I've posted a response on my blog:

http://jcesar.totumo.net/2007/09/13/d-should-have-real-closures/

Comments?

Thanks

Julio César Carrascal Urquijo wrote:
> Brad Anderson wrote:
>> http://www.hans-eric.com/2007/09/11/d-doesnt-have-real-closures/
> 
> I've posted a response on my blog:
> 
> http://jcesar.totumo.net/2007/09/13/d-should-have-real-closures/
> 
> Comments?
> 
> Thanks

On reddit:

http://programming.reddit.com/new

Walter Bright wrote:
> On reddit:
> 
> http://programming.reddit.com/new

Thank you for posting it. Here's the direct link:

http://programming.reddit.com/info/2oyuz/comments