Feature RDF/JS

[rubensworks]

To do:

• RDFJS data: N3Writer & N3StreamWriter
• RDFJS data: N3Store
• RDFJS data: N3Util

[rubensworks]

N3Writer has been changed in a backwards-compatible way, the only cost of this is a simple typeof term === 'string' check on each term, so performance impact should be minimal.

I can still change it if you prefer a complete breaking change, in which case more invasive internal changes to the writer will need to be done.

[RubenVerborgh]

Thanks @rubensworks, breaking changes are fine with me. v1.0.0 will not be backward compatible.

[rubensworks]

@RubenVerborgh I removed backwards compatibility with the string-based interface of N3Writer. However, internally everything currently still works with the old string-based representation. I believe this will have better performance than using the RDF/JS datastructures for everything internally as well.

[rubensworks]

@RubenVerborgh Everything should be compatible with the RDF/JS interface now.

I had to make some design decisions, such as converting everything to a string-based representation internally, and the way N3Util.expandPrefixedName works.
Please let me know if you agree with these.

For reference, I've updated the TS typings, so you can see there what the (intended) types and signatures are.

[elf-pavlik]

Have you tried running the test suite mentioned in rdfjs/data-model-spec#47 (comment) ?

[rubensworks]

@elf-pavlik Thanks for the suggestion, I'll look into it soon.

[rubensworks]

It looks like the test suite is built around DataFactory. This PR however does not provide a DataFactory implementation, so this can't be tested, unless it should?
@RubenVerborgh Thoughts?

[bergos]

@rubensworks the test suite moved to rdf-data-model. Old documentation is still valid.

[rubensworks]

@RubenVerborgh N3Util now implements the DataFactory interface, as requested in #122.

The test suite from @bergos also succeeds, except for one test regarding default graphs, which I believe is a mistake in the tests (rdfjs-base/data-model#3)

[pietercolpaert]

Is performance worse or similar with the new interface? @rubensworks

[RubenVerborgh]

Slightly worse last time I tested, but acceptable.

[pietercolpaert]

Would this PR make N3.js ready for a new major release?

[RubenVerborgh]

Yes, this will become v1.0.0 when finished. I just desperately need 1 full day to work on this.

[RubenVerborgh]

Thanks for your help, @rubensworks. I've heavily modified the interfaces, so the TypeScript definitions will be obsolete. I've removed usage of the internal representation from most places, and many helper methods from Util are gone.

[rubensworks]

Great! I will look into updating the TS typings soon.