The samples directory has an example of how to use capnp_generate_cpp(): https://github.com/capnproto/capnproto/blob/master/c%2B%2B/samples/CMakeLists.txt#L24
As Stuart said, it only runs when required. On Sun, Jun 9, 2019 at 7:35 AM Stuart Dootson <[email protected]> wrote: > On Sun, 9 Jun 2019 at 14:51, 'Kenton Varda' via Cap'n Proto < > [email protected]> wrote: > >> Hi Adam, >> >> Is cmake running the capnp tool every time, or only when the capnp files >> change? I would suggest configuring it to only re-run the code generation >> when the .capnp files have changed. I don't personally know cmake but it >> surely supports this. >> >> Unfortunately you are correct that there's no good way to forward-declare >> the nested types generated by the capnp tool. >> >> -Kenton >> >> On Fri, Jun 7, 2019 at 6:54 AM Ádám Balázs <[email protected]> wrote: >> >>> Hi all, >>> >>> I try to use Cap'NProto in a CMake based C++ project. CMake runs capnp >>> tool to generate headers/sources and adds them to the project. With this >>> approach I eliminate the inconsistent states, however the generated files >>> are touched every time CMake runs, so the compiler recompiles them during >>> the build. With forward declaration it wouldn't be a big deal, but as far >>> as I understand the generated code I can not forward declare builders and >>> readers since they are nested classes. This is a really unfortunate >>> situation, because the headers using the generated code are used in many >>> components (configurations). Can I somehow forward declare generated >>> classes? Could you advise some technique to solve the described situation? >>> Is it intended to prohibit forward declaration? >>> >>> Thank you in advance: Adam >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Cap'n Proto" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> Visit this group at https://groups.google.com/group/capnproto. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/capnproto/d84ad038-22be-48c0-aac3-050fafc18ca1%40googlegroups.com >>> <https://groups.google.com/d/msgid/capnproto/d84ad038-22be-48c0-aac3-050fafc18ca1%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "Cap'n Proto" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> Visit this group at https://groups.google.com/group/capnproto. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/capnproto/CAJouXQ%3DSbRggayxzM1goybtb-%3D6LsEKMAoVeMJTDH-envvBw%3DQ%40mail.gmail.com >> <https://groups.google.com/d/msgid/capnproto/CAJouXQ%3DSbRggayxzM1goybtb-%3D6LsEKMAoVeMJTDH-envvBw%3DQ%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . > > > There’s a function (CAPNP_GENERATE_CPP) defined in the file > ‘CapnProtoMacros.cmake’ which has CMake code to generate C++ files for > capnp files. It looks like it’s set up properly to only run when required > (by which I mean it uses ‘add_custom_command’ with appropriate output & > dependency parameters set up). I’ve used the same setup for other codegen > tasks, and it’s worked fine. > > The custom command generates the source (by default) in > CMAKE_CURRENT_BINARY_DIR, which is what you’d expect for CMake. It’ll > regenerate the files for a new build directory, but after that should > manage dependencies correctly after that. > > Stuart > > -- > You received this message because you are subscribed to the Google Groups > "Cap'n Proto" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > Visit this group at https://groups.google.com/group/capnproto. > To view this discussion on the web visit > https://groups.google.com/d/msgid/capnproto/CA%2BL%2BJktf_ivaDsTsi%3D6dSUWkDAewKZ1v0%3Dz3O%2BddR4XH1XXnZg%40mail.gmail.com > <https://groups.google.com/d/msgid/capnproto/CA%2BL%2BJktf_ivaDsTsi%3D6dSUWkDAewKZ1v0%3Dz3O%2BddR4XH1XXnZg%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Cap'n Proto" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. Visit this group at https://groups.google.com/group/capnproto. To view this discussion on the web visit https://groups.google.com/d/msgid/capnproto/CA%2BCFaPU%2B49CvNMi8r6AA-HmOM61Wes2BJGUNPSJgxYVnwve%2B7A%40mail.gmail.com.
