Variadic templates and switch statement?

Question

I have the following function which can take N arguments of different types, and forwards them to N functions templated on each individual type, in this manner (example with

Answer 1

Theoretically you could do binary search of parameter index by yourself:

#include 
#include 
#include 
#include 
#include 


template 
using ic = std::integral_constant;

template 
bool func2(T) {
    std::cout<
bool func_impl(ic<0>, ic, std::size_t &, T &&tup) {
    constexpr int index = std::min(N - 1, std::tuple_size{} - 1);
    if (func2>>(std::get(tup))) 
        return true;
    return false;
}

template 
bool func_impl(ic, ic n, std::size_t &counter, T &&tup) {
    if (counter == N - 1) {
        return func_impl(ic<0>{}, n, counter, std::forward(tup));
    }
    if (counter < N) {
        return func_impl(ic{}, ic{}, counter, std::forward(tup));
    } else {
        return func_impl(ic{}, ic{}, counter, std::forward(tup));
    }
}

template 
bool func(std::size_t& counter, Ts&&... xs) {
    return func_impl(ic{}, ic{}, counter, std::forward_as_tuple(xs...));
}

int main() {
   std::size_t i = 0;
   func(i, 1, 2, 3, 4); 
}

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