Gain insights into the C++ keyword 'const,' its usage in various contexts, and implications when returning pointers and references. Learn about preventing accidental data changes.

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In this course, you will learn about the C++ keyword const and its behaviour under different usage conditions, including local, global and static contexts. This course will help you to understand const and its implications when you attempt to return pointers and references in C++. By the end of the course, you will have a solid grip on const and its usage in preventing any accidental change of data.

Secure Coding Practices in C++: A Deep Dive into const

In this chapter, we learned about `const` return types. We saw that simply returning `const` values doesn't make much sense and in fact  it might even hurt the performance.

* Returning a `const&` is dangerous because it might result in a dangling reference and a segmentation fault.

* We can return values with `const&` if we know that the returned object will be available as long as its reference will be used and a copy would be expensive.

* `const` pointers are a bit more varied as both the pointer and the pointed value can be declared `const`. As we saw, the pointer’s constness is ignored for return types, so we should only return `const T*` pointers if we want to bring some constness to our return values.

Get a recap of all the concepts learned in this chapter.

Introduction

Arguments using const

Local Variables

Local Members

Functions

Return Types

const Parameters

const and Smart Pointers

Rvalue References

Summary

Key Takeaways