Try/Catch

Overview

The `try` block contains the code that might fail. The `throw` statement signals that an error occurred. The `catch` block catches the thrown error and handles it.

Syntax

cpp

try {
    int denominator = 0;
    if (denominator == 0) {
        throw "Cannot divide by zero!"; // Throwing a string literal
    }
    cout << 10 / denominator;
} 
catch (const char* errorMessage) {
    cout << "Error Caught: " << errorMessage << endl;
}

Common Pitfalls

Throwing an exception inside a destructor. If a destructor throws an exception while the stack is already unwinding from a previous exception, the program will call `std::terminate()` and crash instantly.

Interview Tips

When an exception is thrown, the program skips all remaining code in the `try` block and jumps directly to the matching `catch` block (this process is called stack unwinding).

Real-World Example

Handling basic division errors.

example

cpp

#include <iostream>
using namespace std;

int main() {
    int a = 10, b = 0;
    
    try {
        if (b == 0) throw 404; // Throwing an integer
        cout << a / b << endl;
    } 
    catch (int errorCode) {
        cout << "Fatal Error! Code: " << errorCode << endl;
    }
    
    cout << "Program continues running safely.\n";
    return 0;
}

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