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Deep Dive into string_view
string_view is one of those types C++17 gave us that looks disarmingly simple but hides real subtleties — it is nothing more than a pointer plus a length, yet it can replace a large number of const std::string& parameters and eliminate unnecessary string allocations. Used carelessly, however, it introduces fatal problems such as dangling references and missing null termination. In this chapter we take string_view apart from first principles to performance to pitfalls, until every facet of it is thoroughly clear.