Question about alias and getOverloads

[uranuz]

Thanks for advice ;) This looks like some `standard trick` that 
is yet not learnt or forgoten by me personally. The key was in 
using `parent` trait. This is what I failed to think of. This is 
working as expected:
//-----
import std;
import core.thread;
import std.meta: AliasSeq;

void foo(string param1) {}
void foo(string param1, int param2, bool param3) {}

template Bar(alias Func)
{
     alias Bar = __traits(getOverloads, __traits(parent, Func), 
__traits(identifier, Func));
}

void main()
{
	import std.traits: fullyQualifiedName, Parameters;
     import std.conv: text;
     static foreach( It; Bar!foo ) {
     	pragma(msg, fullyQualifiedName!It ~ "/" ~ 
(Parameters!It).length.text);
     }
}
//-----
Output:
onlineapp.foo/1
onlineapp.foo/3
//-----

So as far as I understand alias template parameter gives access 
to all of items of overload set as I was expecting. The only 
problem is that I didn't found something about it in 
specification about templates:
https://dlang.org/spec/template.html