Comment by gaxun | Hacker News Reader

Comment by gaxun | Hacker News Reader

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I spent some time attempting to work with the W3C Web Annotation Data Model. That data model is serialized as JSON-LD.

After spending about 50 hours reading the documents and attempting to implement some of it, I have a general idea what JSON-LD is.

I wasn't really trying to achieve anything, so I basically quit once something seemed opaque enough I couldn't figure it out in a short period of time. When I visited the JSON-LD Test Suite page to see what implementations are expected to do [0], I found:

> Tests are defined into compact, expand, flatten, frame, normalize, and rdf sections

I had a hard time figuring out what each of these verbs meant, and they were about all that the various implementations I found did. For example, the term normalize doesn't even appear in the JSON-LD 1.0 specification [1]. shrug I'm sure I could have figured out more if I spent the time to actually read the whole thing and all the related documents.

[0]: https://json-ld.org/test-suite/

[1]: https://www.w3.org/TR/json-ld

JSON-LD is RDF. Or rather is what RDF would look like if it was serialized in JSON instead of XML. If you look from the Semantic Web angle JSON-LD is just a serialization format, like e.g. Turtle, but using JSON as JSON is popular nowadays.

Sometimes I wonder why this is not said directly, probably because Semantic Web and RDF are passe now.

Actually the post's author addresses this point:

> I made it a point to not mention RDF at all in the JSON-LD 1.0 specification because you didn’t need to go off and read about it to understand what was going on in JSON-LD.

...

> Tests are defined into compact, expand, flatten, frame, normalize, and rdf sections

These are just sub-formats of JSON-LD, information represented is the same but JSON looks a little bit different. Some sub-formats are easier for tools to process, some are better for humans.

> Sometimes I wonder why this is not said directly

There are multiple flavours of RDF and I think json-ld only supports a subset of one of them. Its been a while since I read the spec but I believe there are various fudges with lists, reification and datatype coercion.

Any time I get close to an RDF stack I find its a broken mess. Its complexity seems to almost guarantee incompatibility instead of interoperability.

> Sometimes I wonder why this is not said directly, probably because Semantic Web and RDF are passe now.

It seems to me that on one hand JSON-LD wanted to bootstrap the network effects by bringing along people who were doing RDF both technically (the JSON-LD spec says "JSON-LD is a concrete RDF syntax as described in [RDF11-CONCEPTS].") and socially (published by the RDF WG), but on the other hand the negative brand equity of RDF is recognized as an obstacle for bringing along even more people, hence the OP professing "Hate the Semantic Web" and "Kick RDF in the Nuts".

It's kinda weird how mentioning the RDF connection of JSON-LD in the sense of past experiences with RDF having any bearing on JSON-LD is treated as a social no-no. Despite the above-quoted bit from the spec saying "JSON-LD is a concrete RDF syntax as described in [RDF11-CONCEPTS].", we are supposed to play along with JSON-LD totally having nothing to do with RDF.

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