stdexcept

Header: <stdexcept>

The <stdexcept> header is part of the C++ Standard Library and defines a set of standard exception classes. These exceptions can be used by both the library itself and C++ programs to report common errors.

Key Characteristics

• Provides a set of standard exception classes derived from std::exception
• Divides exceptions into two main categories: logic errors and runtime errors
• Offers a consistent way to handle and report errors in C++ programs
• Exceptions defined here are used throughout the C++ Standard Library

Exception Classes

Logic Errors (derived from std::logic_error)

1. std::logic_error: Base class for logic errors
2. std::domain_error: Domain error exception
3. std::invalid_argument: Invalid argument exception
4. std::length_error: Length error exception
5. std::out_of_range: Out-of-range exception

Runtime Errors (derived from std::runtime_error)

1. std::runtime_error: Base class for runtime errors
2. std::range_error: Range error exception
3. std::overflow_error: Overflow error exception
4. std::underflow_error: Underflow error exception

Example 1: Handling Invalid Arguments

#include <iostream>
#include <stdexcept>
#include <cmath>

double calculateSquareRoot(double number) {
    if (number < 0) {
        throw std::invalid_argument("Negative input is not allowed");
    }
    return std::sqrt(number);
}

int main() {
    try {
        std::cout << calculateSquareRoot(-9) << std::endl;
    } catch (const std::invalid_argument& e) {
        std::cerr << "Error: " << e.what() << std::endl;
    }
    return 0;
}

Explanation

• Demonstrates the use of std::invalid_argument for input validation
• Shows how to throw and catch a standard exception

Example 2: Using Out-of-Range Exception

#include <iostream>
#include <stdexcept>
#include <vector>

int main() {
    std::vector<int> vec = {1, 2, 3};
    try {
        std::cout << vec.at(5) << std::endl;
    } catch (const std::out_of_range& e) {
        std::cerr << "Out of range error: " << e.what() << std::endl;
    }
    return 0;
}

Explanation

• Shows how std::out_of_range is used in the Standard Library (vector::at)
• Illustrates catching and handling a specific exception type

Additional Considerations

• Use these standard exceptions when appropriate to maintain consistency with the C++ Standard Library
• Custom exception classes can be derived from these standard exceptions for more specific error handling
• Always catch exceptions by const reference to avoid slicing
• Consider using noexcept specifier for functions that don't throw exceptions

Summary

The <stdexcept> header provides a set of standard exception classes that form the foundation of error handling in C++. By using these predefined exceptions, developers can create more consistent and maintainable error-handling code. The header defines exceptions for both logic errors (issues that could be detected at compile time) and runtime errors (issues that can only be detected during program execution). Proper use of these exceptions can lead to more robust and reliable C++ programs.

Citations:

[1] https://cplusplus.com/reference/stdexcept/ [2] https://en.cppreference.com/w/cpp/header/stdexcept [3] https://stdcxx.apache.org/doc/stdlibref/stdexcept-h.html [4] https://www.geeksforgeeks.org/exception-header-in-cpp-with-examples/ [5] https://stdcxx.apache.org/doc/stdlibug/18-4.html [6] https://www.machinet.net/tutorial-eng/common-uses-of-stdexcept-in-modern-cpp-programming [7] https://www.tutorialspoint.com/cpp_standard_library/stdexcept.htm