Log It, Then Pass It On

1#include <iostream>
2#include <stdexcept>
3#include <string>
4 
5void sendEmail(const std::string& to) {
6    if (to.find('@') == std::string::npos) {
7        throw std::invalid_argument("bad address: " + to);
8    }
9    std::cout << "sent to " << to << "\n";
10}
11 
12void notify(const std::string& to) {
13    try {
14        sendEmail(to);
15    } catch (const std::invalid_argument& e) {
16        std::cout << "notify log: " << e.what() << "\n";
17        throw;
18    }
19    std::cout << "notify finished\n";
20}
21 
22int main() {
23    try {
24        notify("ana@example.com");
25        notify("bob.example.com");
26        notify("cy@example.com");
27    } catch (const std::invalid_argument& e) {
28        std::cout << "main handled: " << e.what() << "\n";
29    }
30    return 0;
31}