Gain insights into C++20 Concepts to enhance type safety. Delve into creating compiler-checked criteria for templates and improving error clarity for seamless generic code development.

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clang-gcc.tar.gz

c++20

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This course will walk you through the newest version of C++ 20, C++ Concepts.

You will go through one of the most significant new features in C++20, which is Concepts. Concepts allow you to create compiler-checked criteria for template parameters, revolutionizing the way you think about and develop generic code. You can use them to provide both syntactic and semantic requirements. They also allow you to explicitly express your goal in the type system. If something goes wrong, you'll get a clear error message from the compiler.

While useful, Concepts can be difficult to apply and even confusing sometimes. This course provides you with the knowledge you need to overcome these obstacles and move on to more complex topics.

Let's get started.

C++ Concepts: Improve Type Safety with C++ 20


# Problem
Write a function that takes two integer numbers as parameters and returns the greatest common divisor (GCD) of two numbers.

# Restriction
We can only use a template function based on the `requires` clause.

## Input
Two integer numbers `a` and `b`, as shown below
```c++
a = 3, b = 9
```

## Output
A real number, as shown below.
```c++
3
```

## Sample main function

```c++
int main()
{
    std::cout<<gcd(3,9)<<'\n';
}
```

> **Note**: We don’t need to write the main function in the code below.


## Challenge
Try it yourself first. If you have trouble getting to the solution, you can always press the “Show Solution” button to see how to solve the problem. We’ll go through the in-depth solution in the next lesson.

Good luck!

Let’s try to solve the GCD problem by using the <requires> clause.

Introduction

The Concept Behind C++ Concepts

Four Ways to use Concepts in Functions

C++ Concepts with Classes

Concepts Shipped with the C++ Standard Library

How to Write Your Own C++ Concepts

How to Use C++ Concepts in Real Life

Summary

Challenge - GCD of Two Integers Using the <requires> Clause

Problem