The following code compiles and runs correctly but gives a warning:
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#include<iostream>
using namespace std;
template<class T>
T sum(T value) {
return value;
}
template<class T, class ... U>
auto sum(T value, U ... values) {
return value + sum(values ...);
}
int main() {
cout << sum(1, 2, 4.6) << endl;
cout << sum(1, "abcde", 2) << endl;
}
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$ g++ -std=c++11 pack.cpp
pack.cpp:11:31: warning: â??sumâ?? function uses â??autoâ?? type specifier
without trailing return type [enabled by default]
auto sum(T value, U ... values) {