see #2: add std::initializer_list for printf back

This commit is contained in:
Changkun Ou
2019-07-11 11:15:01 +02:00
parent dd8cf90bbe
commit 7a4a605e0f
2 changed files with 37 additions and 4 deletions

View File

@@ -17,7 +17,7 @@ void magic(Ts... args) {
}
// 1 recursive parameter unpack
// 1. recursive parameter unpack
template<typename T0>
void printf1(T0 value) {
std::cout << value << std::endl;
@@ -28,13 +28,22 @@ void printf1(T value, Ts... args) {
printf1(args...);
}
// 2 variadic template parameter unfold
// 2. variadic template parameter unfold
template<typename T0, typename... T>
void printf2(T0 t0, T... t) {
std::cout << t0 << std::endl;
if constexpr (sizeof...(t) > 0) printf2(t...);
}
// 3. parameter unpack using initializer_list
template<typename T, typename... Ts>
auto printf3(T value, Ts... args) {
std::cout << value << std::endl;
(void) std::initializer_list<T>{([&args] {
std::cout << args << std::endl;
}(), value)...};
}
int main() {
magic();
magic(1);
@@ -42,5 +51,6 @@ int main() {
printf1(1, 2, "123", 1.1);
printf2(1, 2.3, "abc");
printf3(111, 123, "alpha", 1.2);
return 0;
}