Comment by magicalhippo
5 months ago
> Yeah they fixed that, but there's other parts of the spec that are basically unworkable
Yeah it just made me chuckle cause it was such an obvious oversight and a fun way of pointing it out. That said I totally get that writing specs are hard, so not dissing the authors as such.
> There's no reason an MP implementation has to be slower than a CBOR implementation.
Yeah that also struck me. Like ok that CBOR library might be faster than that MP library, but could be either is just missing some optimizations. And it didn't look like there were orders-of-magnitude differences in either case.
Anyway I've only looked at CBOR and MessagePack when I dabbled with some microcontroller projects. I found both to be too big, ie couldn't find a library suitably small, either compiled size or memory requirements or both. So I ended up with JSON for those due to that. Using a SAX-like parser I could avoid dynamic allocations entirely (or close enough).
> That said I totally get that writing specs are hard, so not dissing the authors as such.
Oh definitely. Yeah maybe I come off as anti-spec or something, but in this case I just think MP was really well thought out, and then Bormann hung a bunch of stuff on it that really wasn't, and I'm salty haha.
> Anyway I've only looked at CBOR and MessagePack when I dabbled with some microcontroller projects. I found both to be too big, ie couldn't find a library suitably small, either compiled size or memory requirements or both. So I ended up with JSON for those due to that. Using a SAX-like parser I could avoid dynamic allocations entirely (or close enough).
Whaa? I wrote an MP implementation specifically for this use case: https://github.com/camgunz/cmp. JSON parsing terrifies me; there was some table of tons of JSON (de)serializers with all their weirdo bugs that I never would've thought of. There are probably pretty good test suites now though? I've never looked.
> I wrote an MP implementation specifically for this use case
Perhaps I missed that, can't recall. Will definitely try (again) tho, looks very promising.
As for parsing JSON, the upside is that's its trivial to debug over serial, both viewing and sending, and in my case I could assume limited shenanigans and fail hard if there were issues.
> As for parsing JSON, the upside is that's its trivial to debug over serial, both viewing and sending, and in my case I could assume limited shenanigans and fail hard if there were issues.
Totally yeah, text formats are way easier to work with. This is a very undersold benefit of JSON.