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Frozen - An header-only, constexpr alternative to gperf for C++14 users

by Serge Guelton

From the article:

An open source, header-only library that provides fast, immutable, constexpr-compatible implementation of std::set, std::map, std::unordered_map and std::unordered_set to C++14 users. It can be used as an alternative to gperf...