Introduction

In the chapter about Removed or Fixed Language Features, we focused only on the language side. But The Standard Library was also cleaned-up in C++17. This chapter shows the list of most [^mostdepr] of the removed or deprecated types and utilities.

[^mostdepr]: If you want to find the list of all deprecated elements, you can check “Annex D Compatibility features” of the Standard, for example under this link: https://timsong-cpp.github.io/cppwp/n4659/depr

In this chapter, you’ll learn:

• Why auto_ptr was removed and why you should stick with smart pointers
• Why std::random_shuffle algorithm was removed and what’s a better alternative for it
• How to implement custom iterator and not derive from deprecated std::iterator type
• What are the other smaller elements that were deprecated or removed

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Let’s get started with auto_ptr.