On Wed, Oct 31, 2018 at 2:19 PM Adam Cozzette <[email protected]> wrote:
> I'm not sure how soon we can expect the proto2 support in C#. Jie, do you > happen to know how close it is to being complete? > I don't think it will be very soon. We do not have people in google working on C# (I only review PRs). Only one person from third party working on proto2 support. So far, field presence has been submitted and group is ongoing. extension and default value are still missing > But if you're just trying to generate C# code at build time, I was > thinking you could also use for example a C++ binary to generate the C# > code, without needing SWIG or anything. > > It would go something like this: > - Run "protoc --descriptor_set_out=... path/to/my.proto > descriptors.out" > - Run your C++ program which reads in the descriptors and generates C# code > - Then build the C# project as usual > > On Wed, Oct 31, 2018 at 11:11 AM Michael Powell <[email protected]> > wrote: > >> On Wed, Oct 31, 2018 at 1:57 PM Adam Cozzette <[email protected]> >> wrote: >> > >> > +Jie Luo who knows the most about C# >> > >> > The one thing that might be a problem is that C# does not yet have full >> support for proto2, though that work is in progress (see this most recent >> pull request). That could make it hard to parse the descriptor protos from >> C#, since descriptor.proto is a proto2 file. On the other hand, if you're >> using proto3 you could also forget about parsing the descriptors yourself >> but just use protobuf reflection to examine your messages within a C# >> program. >> >> Herein lies the rub... The proto I am dealing with is v2 at the >> moment, yes. How soon do you think the PR would be verified, accepted, >> etc? >> >> > When you say you want to generate boilerplate, do you mean that you >> want to generate C# code at build time? If so then another option is to >> just use another language like C++ or Java to output your C# code. >> >> Exactly. I am working from a .proto file and want to output some >> non-message adapter type stuff for a Google.OrTools C# adapter I'm >> working on, which uses this internally. I could churn through the >> .proto manually by hand, but I figure this is a prime candidate for a >> build-time code generation approach, particularly with adequate proto >> buffer spec comprehension. >> >> In terms of introducing another language, you mean with something like >> SWIG comprehension? If it's fairly seamless, I may consider that, as >> well. In a word diagram, something like this: >> >> Proto2 -> C++ -> SWIG -> C# -> Code Gen >> >> That's a bit of a pipeline, but it may be doable. >> >> > On Wed, Oct 31, 2018 at 10:26 AM Michael Powell <[email protected]> >> wrote: >> >> >> >> On Wed, Oct 31, 2018 at 1:17 PM Adam Cozzette <[email protected]> >> wrote: >> >> > >> >> > I think that specification has suffered a little bit of neglect >> (sorry about that), because in practice our C++ parser is really the de >> facto standard and we have not recently made an effort to go through and >> make sure the official spec matches it perfectly. My reading of that string >> (/[^\0\n\\]/) is that it's a regular expression saying "any character other >> than null, newline, or backslash." But in general I would say the best bet >> is to resolve ambiguities by looking at what the C++ parser does. >> >> >> >> Thanks for that bit of clarification. >> >> >> >> > By the way, have you considered just reusing the C++ parser that's >> included in protoc? You can call protoc with the --descriptor_set_out flag >> to have it parse your .proto file and produce a serialized >> FileDescriptorSet proto as output. Then at that point it's easy to parse >> the descriptors using just about any language we support, and that should >> give you all the information you need, without the need for a new .proto >> file parser. >> >> >> >> Good point, it's a possibility? Does it protoc to C#? It would be less >> >> difficult, I think, for me to Reflect through that and generate the >> >> boilerplate that I want, probably, than spinning up a full on parser >> >> replete with its AST. >> >> >> >> > On Wed, Oct 31, 2018 at 9:23 AM Michael Powell < >> [email protected]> wrote: >> >> >> >> >> >> On Wed, Oct 31, 2018 at 12:22 PM Michael Powell < >> [email protected]> wrote: >> >> >> > >> >> >> > Concerning Constant, literally from the v2 spec: >> >> >> >> >> >> Rather, Syntax section, excuse me... >> >> >> >> >> >> > syntax = "syntax" "=" quote "proto2" quote ";" >> >> >> > >> >> >> > Do I read that correctly you can expect either 'proto2' or >> "proto2", >> >> >> > but never 'proto2" nor "proto2' ? >> >> >> > >> >> >> > If accurate, that just seems to me to be lazy spec authorship... >> >> >> > >> >> >> > Thanks! >> >> >> > On Wed, Oct 31, 2018 at 12:07 PM Michael Powell < >> [email protected]> wrote: >> >> >> > > >> >> >> > > Hello, >> >> >> > > >> >> >> > > I am writing a parser for the Proto language specification >> starting >> >> >> > > with v2. I need a little help interpreting one of the lines if >> you >> >> >> > > please: >> >> >> > > >> >> >> > > In the "String literals" section, what does this mean: >> >> >> > > >> >> >> > > charValue = hexEscape | octEscape | charEscape | /[^\0\n\\]/ >> >> >> > > >> >> >> > > Specifically, the trailing list of character soup? I want to >> say that >> >> >> > > there are escaped characters in the sequence? Or am I to take >> that >> >> >> > > string literally? Or notwithstanding the enclosing forward >> slashes? >> >> >> > > >> >> >> > > Thanks much in advance! >> >> >> > > >> >> >> > > Best regards, >> >> >> > > >> >> >> > > Michael Powell >> >> >> >> >> >> -- >> >> >> 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 post to this group, send email to [email protected]. >> >> >> Visit this group at https://groups.google.com/group/protobuf. >> >> >> For more options, visit https://groups.google.com/d/optout. >> > -- 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 post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/protobuf. 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