пн, 12 авг. 2019 г. в 23:51, Adam Cozzette <[email protected]>:
> Proto3 doesn't have a concept of field presence for singular primitive > fields, so for example there is no difference between an integer field set > to 0 and that same field being unset entirely. > But in this case it will be impossible to distinguish absence of a field (for example, when changing message format) from the fact that the field is zero and this zero is one of legitime field value? Is there any explanation/rationale for this? > As a result there shouldn't be has_foo() methods for singular primitive > fields, and that is how Google's protobuf libraries work with proto3. There > are has_() methods for embedded message fields, though (since those are not > considered primitive fields). > > On Sun, Aug 11, 2019 at 11:08 PM Denis Feklushkin < > [email protected]> wrote: > >> Hello! >> >> There is a Protobuff 3 implementation for D: >> https://github.com/dcarp/protobuf-d/ >> >> Its author and I am diverged in the interpretation of the Proto3 >> documentation: >> >> Is it necessary to implement something like has_foo() method as in >> Googles's Protobuf C++ and Dart libraries or it is violates protocol >> version 3 and leaved in official libraries only for backward compatibility? >> >> Can someone reasonably support this or that opinion? >> >> Discussion beginned here: >> https://github.com/dcarp/protobuf-d/issues/21 >> >> Thanks! >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Protocol Buffers" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/protobuf/3f826c6a-c67e-4291-9b36-4922180dd7e3%40googlegroups.com >> <https://groups.google.com/d/msgid/protobuf/3f826c6a-c67e-4291-9b36-4922180dd7e3%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/protobuf/CAHY2gWfYXmgLGmEnkLMRQzJC9dK_JeGAkUu03diV-tBobNEEZg%40mail.gmail.com.
