Can this write blank nodes with multiple predicate/object pairs?

[edwardsph]

The output I am looking for is:

[ ] <a> <b> ;
    <c> <d> .

or

[
  <a> <b> ;
  <c> <d> 
] .

The workaround I have found is obviously not intended as it uses internal functions:

writer._write(writer._encodeIriOrBlank(writer.blank([
  { predicate: namedNode('a'), object: namedNode('b') },
  { predicate: namedNode('c'), object: namedNode('d') },
])));
writer._write('.\n');

This produces the second style output.

[jeswr]

I wouldn't think so as the design goal of this library is stream writing rather than pretty-printing.

[edwardsph]

I think it would still fit with the design if there was something like addBlank().

There are test cases where the blank node and its contents are a subject, or the blank node is a graph:

N3.js/test/N3Writer-test.js

Lines 511 to 533 in 075e606

	it('should serialize triples with a one-triple blank node as subject', done => {
	const writer = new Writer();
	writer.addQuad(writer.blank(new NamedNode('a'), new NamedNode('b')), new NamedNode('c'), new NamedNode('d'));
	writer.addQuad(writer.blank({ predicate: new NamedNode('a'), object: new NamedNode('b') }), new NamedNode('c'), new NamedNode('d'));
	writer.addQuad(writer.blank([{ predicate: new NamedNode('a'), object: new NamedNode('b') }]), new NamedNode('c'), new NamedNode('d'));
	writer.end((error, output) => {
	output.should.equal('[ <a> <b> ] <c> <d>.\n' +
	'[ <a> <b> ] <c> <d>.\n' +
	'[ <a> <b> ] <c> <d>.\n');
	done(error);
	});
	});
	it('should serialize triples with an empty blank node as graph', done => {
	const writer = new Writer();
	writer.addQuad(new NamedNode('a'), new NamedNode('b'), new NamedNode('c'), writer.blank());
	writer.addQuad(new NamedNode('a'), new NamedNode('b'), new NamedNode('c'), writer.blank([]));
	writer.end((error, output) => {
	output.should.equal('[] {\n<a> <b> <c>\n}\n' +
	'[] {\n<a> <b> <c>\n}\n');
	done(error);
	});
	});

[RubenVerborgh]

The output I am looking for is:

[ ] <a> <b> ;
    <c> <d> .

This one should have worked:

import { Writer, DataFactory } from './lib/index.js';

const writer = new Writer();
const { namedNode } = DataFactory;

const blank = writer.blank();
writer.addQuad(blank, namedNode('a'), namedNode('b'));
writer.addQuad(blank, namedNode('c'), namedNode('d'));

writer.end((err, result) => console.log(result));

but it returns this at the moment:

[] <a> <b>.
[] <c> <d>.

Let me check if this is an easy fix.

[RubenVerborgh]

Fix published as v1.17.1.