templatized delegate

[Alex via Digitalmars-d-learn]

Hi, all
I have a question, how to handle a templated delegate. However, 
I'm not sure, if I'm going in the right direction, so I have 
three examples, and my question is about the third.

1. Here, a struct with an alias is defined and on its creation 
the delegate get known to the struct. Everything is ok.

struct A(alias dg)
{
	auto fun(int i, string s)
	{
		return dg(i, s);
	}
}

void main()
{
	
	auto dlg(int i, string s)
	{
		import std.stdio;
		writeln(i, " ", s);
	}
	auto a = A!dlg();
	a.fun(5, "a");
}

2. Now, I want to store the delegate in another struct. If I want 
to do this, I have to define the pointer as static. This is not 
intended at the beginning, but it's ok, as I know, that the 
delegate would be the same across all instances of B.

struct A(alias dg)
{
	auto fun(int i, string s)
	{
		return dg(i, s);
	}
}

struct B
{
	A!dlgptr a;
	static void delegate(int, string) dlgptr; // here, without the 
"static" "need 'this' to access member dlgptr" rises
	this(void delegate(int, string) dlg)
	{
		dlgptr = dlg;
	}
	void fun(int i, string s)
	{
		a.fun(i, s);
	}
}

void main()
{
	auto dlg(int i, string s)
	{
		import std.stdio;
		writeln(i, " ", s);
	}
	auto b = B(&dlg);
	b.fun(5, "a");
}

3. Now the hard stuff comes. I want to templatize my delegate.
struct A(alias dg)
{
	auto fun(T, U...)(T t, U u)
	{
		return dg!(T, U)(t, u);
	}
}

struct C
{
	A!dlgptr a;
	
	/* static? */ template dlgptr(T, U...)
	{
		/* static? */ void delegate(T, U) dlgptr;
	}

	this(???)
	{
		???
	}
	
	void fun(T, U...)(T t, U args)
	{
		dlgptr!(T, U)(t, args);
	}
}

void main()
{
	auto dlg(T, U...)(T t, U u)
	{
		import std.stdio;
		writeln(t, " ", u);
	}
	
	auto c = C(???);
	c.fun(5, "a"); // exception, obviously, as C is not initialized 
properly
	
	A!dlg a;
	a.fun(5, "a"); //Error: function test92.A!(dlg).A.fun!(int, 
string).fun cannot get frame pointer to test92.main.dlg!(int, 
string).dlg
}

Here, nothing works any more... I have no idea, what to pass to 
the struct C, as a template is not an lvalue. But even the direct 
initialization of A doesn't work...

By the way, I found
http://forum.dlang.org/post/xiycyjndqzbohjtjfjvh@forum.dlang.org
and
http://www.digitalmars.com/d/archives/digitalmars/D/learn/delegate_template_and_alias_31092.html
these both go into the right direction I think... but don't see, 
how to reformulate them...
Thanks in advance :)