I'm learning template, and have this program:
#include <iostream>
class Beef {};
class Chicken {};
template<class Raw>
class Ingredient {};
template<class Raw>
class Menu {
public:
void cook(const Ingredient<Raw> ingredient) {
std::cout<<"cooking\n";
}
};
int main() {
auto beef = Ingredient<Beef>();
auto chicken = Ingredient<Chicken>();
auto menu = Menu<Chicken>();
menu.cook(chicken);
return 0;
}
This program works well so far when Meun is given only 1 template parameter and function cook takes also 1 parameter. Then I got stuck when extend Menu to accept more than 1 template parameter:
template<class... Raw>
class Menu {
public:
void cook() {
std::cout<<"cooking\n";
}
};
How do I extend cook accordingly to accept arbitrary length of argument and also automatically type check during compile time? Ideally I hope to use the APIs in such a way:
auto beef = Ingredient<Beef>();
auto chicken = Ingredient<Chicken>();
auto lamb = Ingredient<Lamb>();
auto menu = Menu<Chicken, Beef>();
menu.cook(chicken, beef); // compile
menu.cook(beef, chicken); // also compile
menu.cook(beef); // error
menu.cook(beef, chicken, lamb); // error
How should I implement cook()?
