C++14 and C++17 Features

What You’ll Learn 📚

• The key features introduced in C++14 and C++17
• How to apply these features in your code
• Common pitfalls and how to avoid them
• Practical examples to solidify your understanding

Introduction to C++14 and C++17

C++ is a powerful language that continuously evolves to meet modern programming needs. C++14 and C++17 introduced several enhancements and new features that make coding more efficient and expressive. Let’s explore these features step-by-step.

Key Terminology

• Lambda Expressions: Anonymous functions you can use to write inline functions.
• constexpr: A keyword used to define expressions that can be evaluated at compile time.
• auto: A keyword that allows the compiler to automatically deduce the type of a variable.

Getting Started with C++14

1. Binary Literals

#include <iostream>

int main() {
    // Using binary literals
    int binary = 0b1101; // 13 in decimal
    std::cout << "Binary 0b1101 is " << binary << " in decimal." << std::endl;
    return 0;
}

2. Generic Lambdas

#include <iostream>

int main() {
    // Generic lambda
    auto add = [](auto a, auto b) { return a + b; };
    std::cout << "Sum: " << add(5, 3) << std::endl;
    std::cout << "Sum: " << add(2.5, 3.5) << std::endl;
    return 0;
}

Exploring C++17 Features

1. std::optional

#include <iostream>
#include <optional>

std::optional<int> findEven(int num) {
    if (num % 2 == 0) {
        return num;
    } else {
        return std::nullopt;
    }
}

int main() {
    auto result = findEven(4);
    if (result) {
        std::cout << "Even number: " << *result << std::endl;
    } else {
        std::cout << "Not an even number." << std::endl;
    }
    return 0;
}

2. Structured Bindings

#include <iostream>
#include <tuple>

std::tuple<int, double, std::string> getData() {
    return std::make_tuple(1, 3.14, "Hello");
}

int main() {
    auto [id, value, text] = getData();
    std::cout << "ID: " << id << ", Value: " << value << ", Text: " << text << std::endl;
    return 0;
}

Common Questions and Answers

1. What are the main differences between C++14 and C++17?

   C++17 introduced more significant features like std::optional, structured bindings, and std::variant, whereas C++14 focused on refining and extending the features introduced in C++11.

2. How do I enable C++14 or C++17 in my compiler?

   Use the -std=c++14 or -std=c++17 flag when compiling with g++ or clang++.

3. Why should I use std::optional?

   It provides a safer and more expressive way to handle optional values compared to using pointers or special values like nullptr.

4. Can I use C++17 features in older compilers?

   Only if the compiler supports C++17. Check your compiler’s documentation to see which features are supported.

Troubleshooting Common Issues

Ensure your compiler supports the C++ version you’re trying to use. If you encounter errors, check if you’re using the correct flags.

If you’re unsure about a feature, refer to the official C++ documentation or community forums for guidance.

Practice Exercises

• Try using binary literals to represent different numbers and print their decimal equivalents.
• Create a generic lambda that multiplies two numbers and test it with different types.
• Use std::optional to handle a function that might not return a value.

Remember, practice makes perfect! Keep experimenting with these features, and you’ll become more comfortable with them over time. Happy coding! 😊