예외 처리의 기본 개념

#include <iostream>
#include <string>

double safeDivide(double numerator, double denominator) {
    if (denominator == 0) {
        throw std::string("Error: Division by zero is not allowed!"); // std::string 객체 던지기
    }
    return numerator / denominator;
}

int main() {
    double num1 = 10.0;
    double num2 = 2.0;
    double num3 = 0.0;

    // 1. 정상적인 경우
    try {
        double result = safeDivide(num1, num2);
        std::cout << "Result of " << num1 << " / " << num2 << " = " << result << std::endl;
    } catch (const std::string& e) { // std::string 예외를 잡음
        std::cerr << "Caught exception: " << e << std::endl;
    }

    std::cout << "-------------------------------------------\n";

    // 2. 예외가 발생하는 경우
    try {
        double result = safeDivide(num1, num3); // 여기서 예외가 발생
        std::cout << "This line will not be executed." << std::endl; // 실행되지 않음
    } catch (const std::string& e) { // 던져진 std::string 예외를 잡음
        std::cerr << "Caught exception: " << e << std::endl; // 출력: Caught exception: Error: Division by zero is not allowed!
    } catch (int errorCode) { // int 예외는 잡지 않음
        std::cerr << "Caught integer error code: " << errorCode << std::endl;
    } catch (...) { // 다른 모든 예외를 잡음
        std::cerr << "Caught an unexpected exception type." << std::endl;
    }

    std::cout << "Program continues after exception handling.\n";
    return 0;
}

#include <iostream>
#include <string>

void functionC() {
    std::cout << "Inside functionC\n";
    throw "An error occurred in functionC!"; // C-스타일 문자열 예외를 던짐
    std::cout << "This line in functionC will not be executed.\n";
}

void functionB() {
    std::cout << "Inside functionB\n";
    // functionB에는 catch 블록이 없으므로, 예외는 functionA로 전파됨
    functionC();
    std::cout << "This line in functionB will not be executed.\n";
}

void functionA() {
    std::cout << "Inside functionA\n";
    try {
        functionB(); // functionB에서 예외가 발생하여 여기로 전파됨
        std::cout << "This line in functionA's try block will not be executed.\n";
    } catch (const char* message) { // functionA에서 C-스타일 문자열 예외를 잡음
        std::cerr << "Caught exception in functionA: " << message << std::endl;
    }
    std::cout << "Exiting functionA.\n";
}

int main() {
    std::cout << "Starting main...\n";
    functionA();
    std::cout << "Main finished.\n";
    return 0;
}

Starting main...
Inside functionA
Inside functionB
Inside functionC
Caught exception in functionA: An error occurred in functionC!
Exiting functionA.
Main finished.