templatized delegate

[Alex via Digitalmars-d-learn]

On Tuesday, 23 May 2017 at 11:05:09 UTC, Stanislav Blinov wrote:
> void variadic(Args...)(auto ref Args args) { /* ... */ }
>
> This infers whether you pass lvalues or rvalues. If passing 
> further down the chain of such calls is needed, one can use 
> std.functional : fowrard :

yes...

>
> void variadic(Args...)(auto ref Args args) {
>     import std.functional : forward;
>     doStuff(forward!args);
> }
>
> void doStuff(Args...)(auto ref Args args) {
>     /* ... */
> }
>
> 'forward' aliases ref arguments (i.e. passed lvalues) and moves 
> value arguments (i.e. passed rvalues).
>
> If a value is not copyable, it may be move-able (check the docs 
> though, it may not be that either).
>
> void fun(Args...)(auto ref Args args) { /*...*/ }

yes...

> import std.algorithm : move;
>
> auto a = NonCopyable(42);
>
> fun(move(a));
> // or:
> func(NonCopyable(42));

the problem, that I have is, that I would like to use the 
templated approach, but I don't have the function, but only a 
delegate, so:

template(T, U...)
{
     void delegate(ref T neededInput, ref U ignoredInput) dgPtr;
}

Not sure, if this is possible to handle at all...