C++20 Modules: Compile Time Improvements and Practical Experiences

This article shares the author's practical experience using C++20 modules, covering build system choices (Bazel, XMake, Build2, etc.), compile time improvements (25%-45%), and differences from PCH. The author also discusses suitable scenarios for C++20 modules, costs (code refactoring, compiler stability, code completion support, etc.), module wrappers (export-using and extern "C++" styles), and techniques for mixing import and #include. The article concludes with future improvement directions for C++20 modules, such as improving build systems, enhancing code intelligence, resolving cross-platform issues, and highlighting AI's potential in module conversion tool development.