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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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

## How to write abbreviated function templates
There is no need for any template parameter list or `requires` clause when we use abbreviated function templates. We can directly use the concept where the function arguments are enumerated.
```c++
auto add(Number auto a, Number auto b) {
  return a+b;
}
```




Note that after the concept `Number` we put `auto`. As such, we can see that `Number` is a constraint on the type, not a type itself. Imagine if we saw  `auto add(Number a, Number b)`. As users, how would we know that `Number` is not a type, but a concept?

Another thing to note is that, when we use the abbreviated function template, we can mix the types of parameters. We can add an `int` to a `float`.

# How to write abbreviated function templates
There is no need for any template parameter list or `requires` clause when we use abbreviated function templates. We can directly use the concept where the function arguments are enumerated.
```c++
auto add(Number auto a, Number auto b) {
  return a+b;
}
```




Note that after the concept `Number` we put `auto`. As such, we can see that `Number` is a constraint on the type, not a type itself. Imagine if we saw  `auto add(Number a, Number b)`. As users, how would we know that `Number` is not a type, but a concept?

Another thing to note is that, when we use the abbreviated function template, we can mix the types of parameters. We can add an `int` to a `float`.

Get an overview of the abbreviated function templates.

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

The abbreviated Function Templates

How to write abbreviated function templates