How can I pass std::initializer_list in a variable number of arguments?

When we pass an initializer list as a variable argument, we encounter an issue as it lacks a defined type. To resolve this problem, we must explicitly provide the type specifier.

A straightforward method is to create a class with an std::initializer_list constructor and an overloaded operator<<. We can then utilize this class to pass the initializer list as a variable argument, as demonstrated below:

template<typename T>
struct V
{
    V(std::initializer_list<T> v): m_t(v){}
    friend std::ostream& operator<<(std::ostream& os, const V& v)
    {
        std::cout << "{ ";
        for(const auto i: v.m_t)  
        {
             std::cout << i << " "; 
        }
        std::cout << "}";
        return os;
    }
    std::initializer_list<T> m_t;
};
func_( 1,2.5,'a', "Hello", V{10, 20, 30, 40 }); //works now

The provided working demo yields the expected output:

1
2.5
a
Hello
{ 10 20 30 40 }

This method offers customization options to meet specific requirements.