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  • Book Overview & Buying C++17 STL Cookbook
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C++17 STL Cookbook

C++17 STL Cookbook

By : Galowicz
4.3 (15)
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C++17 STL Cookbook

C++17 STL Cookbook

4.3 (15)
By: Galowicz

Overview of this book

C++ has come a long way and is in use in every area of the industry. Fast, efficient, and flexible, it is used to solve many problems. The upcoming version of C++ will see programmers change the way they code. If you want to grasp the practical usefulness of the C++17 STL in order to write smarter, fully portable code, then this book is for you. Beginning with new language features, this book will help you understand the language’s mechanics and library features, and offers insight into how they work. Unlike other books, ours takes an implementation-specific, problem-solution approach that will help you quickly overcome hurdles. You will learn the core STL concepts, such as containers, algorithms, utility classes, lambda expressions, iterators, and more, while working on practical real-world recipes. These recipes will help you get the most from the STL and show you how to program in a better way. By the end of the book, you will be up to date with the latest C++17 features and save time and effort while solving tasks elegantly using the STL.
Table of Contents (11 chapters)
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Inserting items efficiently and conditionally into std::map

Sometimes we want to fill a map with key-value pairs and while filling the map up, we might run into two different cases:

  1. The key does not exist yet. Create a fresh key-value pair.
  2. The key does exist already. Take the existing item and modify it.


We could just naively use the insert or emplace methods of map and see if they succeed. If it doesn't, we have case 2 and modify the existing item. In both cases, insert and emplace create the item which we try to insert, and in case 2 the freshly created item is dropped. We get a useless constructor call in both cases.

Since C++17, there is the try_emplace function, which enables us to create items only conditionally upon insertion. Let's implement a program that takes a list of billionaires and constructs a map that tells us the number of billionaires...

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Tech Concepts
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Programming languages
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C++17 STL Cookbook
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