An issue with using C++20 modules would be cherry-picking into older ATS releases. We could use a cheesy-but-usable macro processor I originally wrote back in the 80s to allow module declaration files to also be used as old-fashioned header files: --- $(module_once) // expands to nothing in C++20 $(export_module parent1 parent2 name) // expands to nothing in C++17 or older, arbitrary number of parents, or none $(export) void foo(); $(module parent1 parent2 name) $(import parent1 parent2 name) --- $(name arg1 arg2 ....) is a macro call. In C++20 these would expand to: --- export module parent1_parent2_name; export void foo(); module parent1_parent2_name; import parent1_parent2_name; --- In C++17 or older these would expand to: --- #pragma once void foo(); #include <parent1/parent2/name.h> #include <parent1/parent2/name.h> ---
---------- Forwarded message --------- From: Masakazu Kitajo <notificati...@github.com> Date: Thu, Sep 26, 2019 at 3:49 AM Subject: Re: [apache/trafficserver] ProxySession cleanup: moving inline functions to .h (#5908) To: apache/trafficserver <trafficser...@noreply.github.com> Cc: Walt Karas <wka...@verizonmedia.com>, Mention < ment...@noreply.github.com> Just for a note and I'm not sure at all, but Module that will be supported on C++20 might resolve some of this complication. https://www.infoq.com/news/2019/07/cpp20-draft-finalized/ Module support will be orthogonal to namespaces and will enable the structuring of large codebases into logical parts without requiring the separation of header and source files.
