Function parameter in variadic template

Question

Is it possible to write a variadic template class with functions as template parameter ?

Theses are valid c++ declarations

template  class foo;

template   class bar;

Would it be possible to do something like

template  class foobar;

I tried a lot of different syntax like

template  class foobar;

and nothing is compiling (I am using gcc 8.1.0 with -std=c++17)

user_2684539 · Answer

Syntax is:

template  class foobar {};

which allows

int f1(int);
int f2(int);

foobar<&f1, &f2, &f1> obj;

Using alias might help you to have more natural syntax:

using f_int_int = int (*)(int);
template  class foobar {};

or even (thanks to Yakk's comment):

template  using id_t = T;
template ...Fs> class foobar {};