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Comment by TheAceOfHearts | Hacker News Reader

Just gonna mention that N3 stands for Notation3 [0]. I'd never heard of it before, and just googling for N3 doesn't lead to any direct results.

My immediate reaction from reading about N3 is that it doesn't seem very easily approachable, especially when compared to JSON. If I type "json" on Google, the first result [1] is a fairly human-friendly spec with a huge list of implementations at the bottom. If I then type "json example" on Google, the first result takes me to a page with lots of examples [2] of JSON side-by-side with XML. In comparison, looking up Notation3 takes me to a w3 spec page for which my first reaction is to say "tl;dr", and looking up examples takes me to two pages [3] [4] which fail to immediately clarify anything.

[0] https://www.w3.org/TeamSubmission/n3/

[1] http://www.json.org

[2] http://www.json.org/example.html

[3] https://www.w3.org/2000/10/swap/Examples.html

[4] https://www.w3.org/2000/10/swap/Primer.html

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N3 in a nutshell is:

-----------------------------------

1) an object has an id and some types. Both are prepended with a ':'

an object definition ends with a '.'

For example:

:teacher1 a :Teacher.

2) an object has property values. Each property name is prepended with a ':'. A property value of type string is surrounded with '"""'. A property value of type integer is as-is. Several values for the same property are separated by ','. Properties are separated by ";"

For example:

:teacher1 :firstNames """John""","""Michael""";

          :lastName """Doe""".

3) Objects properties are properties whose value is another object. Such an object property value is simply the id of the referenced object.

For example:

:teacher1 :studiedAt :Yale, :Stanford, :Miskatonic.

4) Your object definitions may be split into multiple parts.

For example:

:teacher1 a :Teacher.

:teacher1 :firstNames """John""","""Michael""";

          :lastName """Doe""".

:teacher1 :studiedAt :Yale, :Stanford, :Miskatonic.

:Miskatonic a :University.

:Miskatonic :locatedIn :Arkham;

            :name """Miskatonic University""".

:Arkham a :City.

:Arkham :famousTeacher :teacher1.

-----------------------------------

Nothing especially difficult, in my humble opinion.

The great benefit of N3 (and the Semantic Web in general) is that the object definitions can come from separate datasets and be merged into a single graph, because all UUIDs are aligned in the Semantic Web.

The triple double quotes are horrible.

I infer from that statement that the other characteristics of N3 did not troubled you that much.

Oh god, my eyes are completely refusing to count these

This is absolutely optional. You can use " instead. You then need to escape the " as you would in JSON.

Note: This is a completely optional feature of N3:

N3 can also express rules to apply upon data. For example, add this to the above definition:

{ ?x :studiedAt ?y } => { ?y a :EducationalInstitution }.

and that infers the following object definitions:

:Yale a :EducationalInstitution.

:Stanford a :EducationalInstitution.

:Miskatonic a :EducationalInstitution.

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