C++20 Modules Purpose Guide agents through authoring, building, and debugging C++20 modules: named modules vs header units, module partitions, CMake integration, compiler-specific flags, and interoperability with legacy headers. Triggers - "How do I write a C++20 module?" - "How do I import a module in CMake?" - "What's the difference between a named module and a header unit?" - "My module gives 'cannot find module' errors" - "How do I use C++20 modules with Clang?" - "How do I migrate from headers to modules?" Workflow 1. Module concepts overview Named modules are the primary target. Header…