string

My last post "C++20: The Core Language" presented the new features of the C++20 core language. Today, I continue my journey with an overview of the C++20 library.

My last post C++20: The Big Four started with an overview of concepts, ranges, coroutines, and modules. Of course, C++20 has more to offer. Today, let's continue my overview of the core language.

The C++ core guidelines use the term string as a sequence of characters. Consequently, the guidelines are about  C-strings, C++-strings, the C++17 std::string_view's, and std::byte's. 

The purpose of std::string_view is to avoid copying data that is already owned by someone else and of which only a non-mutating view is required. So, this post is mainly about performance.

What's new in the library? A lot. To make the long story short. We get a std::string_view, parallel algorithm of the Standard Template Library, a file system library, and the three new data types std::any, std::optional, and std::variant. Let's look at the details.