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<!DOCTYPE html>
<html lang="en">
<head>
<title>JSON-LD-star</title>
<meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
<script src="https://www.w3.org/Tools/respec/respec-w3c" class="remove" defer></script>
<script src="common/common.js" class="remove" defer></script>
<script class='remove'>
var respecConfig = {
localBiblio: {
"RDFStar": {
"title": "RDF-star and SPARQL-star",
"authors": [
"Olaf Hartig",
"Pierre-Antoine Champin"
],
"publisher": "W3C",
"status": "W3C CG Draft",
"href": "https://w3c.github.io/rdf-star/cg-spec/2021-02-18.html",
"editors": ["Olaf Hartig", "Pierre-Antoine Champin"],
"date": "2021-02-18"
},
"JSON-LD-star-tests": {
"title": "JSON-LD-star Test Suite",
"author": "Gregg Kellogg",
"publisher": "W3C",
"status": "unofficial",
"href": "https://json-ld.github.io/json-ld-star/tests/"
}
},
specStatus: "CG-DRAFT",
copyrightStart: "2020",
shortName: "json-ld-star",
latestVersion: "https://json-ld.github.io/json-ld-star/publications/2021-02-18.html",
prevVersion: "https://json-ld.github.io/json-ld-star/publications/2021-02-18.html",
previousPublishDate: "2021-02-18",
previousMaturity: "CG-DRAFT",
edDraftURI: "https://json-ld.github.io/json-ld-star/",
testSuiteURI: "https://json-ld.github.io/json-ld-star/tests/",
implementationReportURI:"https://json-ld.github.io/json-ld-star/reports/",
github: {
repoURL: "https://github.com/json-ld/json-ld-star/",
branch: "main"
},
doJsonLd: true,
editors: [{
name: "Gregg Kellogg",
url: "http://greggkellogg.net/",
w3cid: "44770"
}, {
name: "Pierre-Antoine Champin",
url: "http://champin.net/",
company: "ERCIM",
companyURL: "https://www.ercim.eu/",
w3cid: 42931,
orcid: "0000-0001-7046-4474",
}],
//previousMaturity: "FPWD",
//previousPublishDate: "1977-03-15",
// Cross-reference definitions
xref: ["json-ld11", "json-ld11-api", "json-ld11-framing"],
group: "cg/json-ld",
wgPublicList: "public-linked-json",
maxTocLevel: 4,
noRecTrack: "true"
};
</script>
<script>
document.addEventListener("DOMContentLoaded", () => {
// Add example button selection logic
for (const button of document.querySelectorAll(".ds-selector-tabs .selectors button")) {
button.onclick = () => {
const ex = button.closest(".ds-selector-tabs");
ex.querySelector("button.selected").classList.remove("selected");
ex.querySelector(".selected").classList.remove("selected");
button.classList.add('selected');
ex.querySelector("." + button.dataset.selects).classList.add("selected");
}
}
// Toggle show/hide changes
for (const elem of document.querySelectorAll(".show-changes")) {
elem.onclick = () => {
if (elem.classList.contains("selected")) {
// Remove highlight class from elements having "changed" class
elem.classList.remove("selected");
for (const changed of document.querySelectorAll(".changed")) {
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}
} else {
// Add highlight class to elements having "changed" class
elem.classList.add("selected");
for (const changed of document.querySelectorAll(".changed")) {
changed.classList.add("highlight");
}
}
}
}
});
</script>
<style>
.hidden { display: none;}
.hl-bold { font-weight: bold; color: #0a3; }
.comment { color: #999; }
table, thead, tr, td { padding: 5px; border-width: 1px; border-spacing: 0px; border-style: solid; border-collapse: collapse; }
table.example {width: 100%;}
.example > pre.context:before {
content: "Context";
float: right;
font: x-large Arial, sans-serif;
color: gray;
border: solid thin black;
padding: 0.2em;
}
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content: "Frame";
float: right;
font: x-large Arial, sans-serif;
color: gray;
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font: x-large Arial, sans-serif;
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.example > pre.turtle:before {
content: "Turtle";
float: right;
font: x-large Arial, sans-serif;
color: gray;
border: solid thin black;
padding: 0.2em;
}
aside.example {
overflow-y: hidden;
}
/* example tab selection */
.ds-selector-tabs {
padding-bottom: 2em;
}
.ds-selector-tabs .selectors {
padding: 0;
border-bottom: 1px solid #ccc;
height: 28px;
}
.ds-selector-tabs .selectors button {
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.ds-selector-tabs pre:not(.preserve), .ds-selector-tabs table:not(.preserve) {
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a.playground {
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a[href].playground {
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.algorithm ol {
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</style>
</head>
<body>
<section id='abstract'>
<p>
This NOTE describes an extension to [[JSON-LD11]], [[JSON-LD11-API]],
and [[JSON-LD11-FRAMING]] to allow arcs in a <a>Linked Data Graph</a> to
be annotated using the [[RDFStar]] model.
</p>
</section>
<section id='sotd'>
<p>
This is an unofficial proposal.
</p>
</section>
<section>
<h2>Introduction</h2>
<p>[[[RDFStar]]] [[RDFStar]] addresses the problem of annotating arcs in a <a>Linked Data Graph</a>
by extending the <a data-cite="RDF11-CONCEPTS#data-model">RDF data model</a> [[RDF11-CONCEPTS]] to allow for triples
to be used as the <a>subject</a>
or <a>object</a> of another <a data-cite="RDF11-CONCEPTS#dfn-rdf-triple">RDF triple</a>.
This note describes an update to the <a data-cite="JSON-LD11#data-model">JSON-LD data model</a>
to allow limited form of a <a data-cite="JSON-LD11#dfn-node-object">node object</a>
to use another <a data-cite="JSON-LD11#dfn-node-object">node object</a> as its node identifier.</p>
<p>The two popular graph-based data models have been RDF [[RDF11-CONCEPTS]] and
<a href="https://en.wikipedia.org/wiki/Graph_database#Labeled-property_graph">Labeled-property Graphs</a>,
which are roughly similar, with the RDF model being more formal in identifying nodes,
datatypes and relationships, while Property Graphs
use a less formal relationship model somewhat similar to JSON. In both models,
nodes are related via edges (AKA arcs), but in Property Graphs,
those edges may themselves be annotated with properties.
This is useful in providing additional metadata and semantics to relationships of the nodes.</p>
<p>Historically, in RDF, this can be simulated through <a href="https://www.w3.org/wiki/RdfReification">Reification</a>,
where a <a>triple</a> is represented by another resource with properties for the <a>subject</a>, <a>predicate</a>, and <a>object</a>,
which allows additional properties to be asserted on that reification node.</p>
<pre class="example turtle"
data-transform="updateExample"
data-content-type="text/turtle"
title="An RDF Triple and its Reification">
<!--
@base <http://example.org/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix : <#> .
:bob :age 42 .
# Reification of previous triple
[
a rdf:Statement;
rdf:subject :bob;
rdf:predicate :age;
rdf:object 42
] .
-->
</pre>
<p>In [[RDFStar]], a <a>triple</a> may act as the <a>subject</a> or <a>object</a> in another <a>triple</a>,
for example, we can modify how certain we are about a relationship as follows:</p>
<pre class="example turtle"
data-transform="updateExample"
data-content-type="text/turtle"
data-options="rdfstar=true"
title="Annotation on an RDF triple">
<!--
@base <http://example.org/> .
@prefix : <#> .
:bob :age 42.
<< :bob :age 42 >> :source <http://example.org/~bob/>.
-->
</pre>
<p>This NOTE explores an extension of JSON-LD which can allow
the value of an `@id` property to be an <a>embedded node</a>,
and the description of an <a>annotation object</a> which serves as
a short-hand when the annotated value also is described
directly in the graph.</p>
</section>
<div class="informative">
<!-- Terms included for referencability, but not displayed -->
<div data-include="common/terms.html"></div>
<div data-include="common/algorithm-terms.html"></div>
</div>
<section id="conformance">
<p>A <a>JSON-LD-star document</a> complies with this specification if it follows
the normative statements in <a href="#grammar-extensions"></a>.
For convenience, normative
statements for documents are often phrased as statements on the properties of the document.</p>
<p>This specification makes use of the following namespace prefixes:</p>
<table class="simple">
<thead><tr>
<th>Prefix</th>
<th>IRI</th>
</tr></thead>
<tbody>
<tr>
<td>ex</td>
<td>http://example.org/</td>
</tr>
<tr>
<td>rdf</td>
<td>http://www.w3.org/1999/02/22-rdf-syntax-ns#</td>
</tr>
<tr>
<td>xsd</td>
<td>http://www.w3.org/2001/XMLSchema#</td>
</tr>
</tbody>
</table>
<p>These are used within this document as part of a <a>compact IRI</a>
as a shorthand for the resulting <a>IRI</a>, such as <code>dcterms:title</code>
used to represent <code>http://purl.org/dc/terms/title</code>.</p>
</section>
<section class="informative">
<h2>JSON-LD-star-specific Terms</h2>
<p>The Following terms are used within specific algorithms.</p>
<dl data-sort>
<dt><dfn data-cite="RDFStar#dfn-dataset">RDF-star dataset</dfn></dt><dd>
An <a>RDF dataset</a> extended to allow the use of an
<a>RDF-star graph</a> instead of a plain <a>RDF graph</a>.
</dd>
<dt><dfn data-cite="RDFStar#dfn-graph">RDF-star graph</dfn></dt><dd>
A set of <a>RDF-star triples</a>.
</dd>
<dt><dfn data-cite="RDFStar#dfn-triple">RDF-star triple</dfn></dt><dd>
An <a data-cite="RDF11-CONCEPTS#dfn-rdf-triple">RDF triple</a> extended to allow an <a>RDF-star triple</a> to be
used in the <a>subject</a> or <a>object</a> position.
</dd>
<dt><dfn >Embedded Node</dfn></dt><dd>
An <a>embedded node</a> is a <a>node object</a> describing exactly one <a>property</a>/value pair.
The <a>node object</a> MAY be identified as with other node objects (including with an <a>embedded node</a>).
The <a>property</a> MUST be either `@type` or an <a>IRI</a>.
The property value MUST be either an <a>IRI</a>, <a>blank node</a>, <a>literal</a> or an <a>embedded node</a>.
An <a>embedded node</a> MAY contain other <a>entries</a> that do not, themselves, create directed-arcs, such
as `@context` or `@index`.
An <a>embedded triples</a> is the representation of an <dfn data-cite="RDFStar#dfn-embedded-triple">embedded triple</dfn>.
</dd>
<dt><dfn>JSON-LD-star document</dfn></dt><dd>
A <a>JSON-LD-star document</a> is a serialization of
an <a>RDF dataset</a> as extended by [[RDFStar]].
</dd>
<dt><dfn>Annotation Object</dfn></dt><dd>
An <a>annotation object</a> is a <a>node object</a> which is the value
of `@annotation` (or an alias). It describes [[RDFStar]] annotations
made on the <a>triple</a> between by its parent <a>node object</a> or <a>value object</a>, and the parent's closest ancestor <a>node object</a>.
</dd>
</dl>
</section>
<section id="basic-concepts" class="informative">
<h2>Basic Concepts</h2>
<p>This specification adds the concepts of an <a>embedded node</a>
and <a>annotation object</a> to JSON-LD in order to add the
ability to make statements about individual <a>triples</a> in an
<a>RDF-star Graph</a>.</p>
<p>An <a>embedded node</a> supports the ability to make one or more statements
about a <a>triple</a>, represented by an <a>embedded node</a>, without that
triple being necessarily considered to be part of the <a>Linked Data Graph</a>.</p>
<p>The following example shows how the value of `@id` can be an
of <a>embedded node</a>, which expresses a single <a>triple</a>:</p>
<aside class="example ds-selector-tabs"
title="Embedded node as subject">
<div class="selectors">
<button class="selected input" data-selects="compacted">Compacted (Input)</button>
<button data-selects="expanded">Expanded</button>
<button data-selects="flattened">Flattened</button>
<button data-selects="turtle">Turtle-star</button>
</div>
<pre class="compacted input selected"
data-transform="updateExample"
data-options="rdfstar=true">
<!--
{
"@context": {
"@base": "http://example.org/",
"@vocab": "http://example.org/"
},
"@id": {
"@id": "bob",
"age": 42
},
"certainty": 0.8
}
-->
</pre>
<pre class="expanded"
data-transform="updateExample"
data-options="rdfstar=true"
data-result-for="Embedded node as subject-compacted">
<!--
[{
"@id": {
"@id": "http://example.org/bob",
"http://example.org/age": [{"@value": 42}]
},
"http://example.org/certainty": [{"@value": 0.8}]
}]
-->
</pre>
<pre class="flattened"
data-transform="updateExample"
data-options="rdfstar=true"
data-flatten
data-result-for="Embedded node as subject-compacted">
<!--
[{
"@id": {
"@id": "http://example.org/bob",
"http://example.org/age": [{"@value": 42}]
},
"http://example.org/certainty": [{"@value": 0.8}]
}]
-->
</pre>
<pre class="turtle"
data-content-type="text/turtle"
data-transform="updateExample"
data-options="rdfstar=true,canonicalize=true"
data-to-rdf
data-result-for="Embedded node as subject-compacted">
<!--
@prefix : <http://example.org/> .
<< :bob :age 42 >> :certainty 0.8e0 .
-->
</pre>
</aside>
<p>An <a>annotation object</a> supports the ability to make one or more statements (annotations)
about a <a>triple</a>, where the <a>triple</a> <em>is</em> considered to be part of the <a>Linked Data Graph</a>.</p>
<aside class="example ds-selector-tabs"
title="Annotating a node">
<div class="selectors">
<button class="selected input" data-selects="compacted">Compacted (Input)</button>
<button data-selects="expanded">Expanded</button>
<button data-selects="flattened">Flattened</button>
<button data-selects="turtle">Turtle-star</button>
</div>
<pre class="compacted input selected"
data-transform="updateExample"
data-options="rdfstar=true">
<!--
{
"@context": {
"@base": "http://example.org/",
"@vocab": "http://example.org/"
},
"@id": "bob",
"age": {
"@value": 42,
"@annotation": {
"certainty": 0.8
}
}
}
-->
</pre>
<pre class="expanded"
data-transform="updateExample"
data-options="rdfstar=true"
data-result-for="Annotating a node-compacted">
<!--
[{
"@id": "http://example.org/bob",
"http://example.org/age": [{
"@value": 42,
"@annotation": [{
"http://example.org/certainty": [{"@value": 0.8}]
}]
}]
}]
-->
</pre>
<pre class="flattened"
data-transform="updateExample"
data-options="rdfstar=true"
data-flatten
data-result-for="Annotating a node-compacted">
<!--
[{
"@id": "http://example.org/bob",
"http://example.org/age": [{"@value": 42}]
}, {
"@id": {
"@id": "http://example.org/bob",
"http://example.org/age": [{"@value": 42}]
},
"http://example.org/certainty": [{"@value": 0.8}]
}]
-->
</pre>
<pre class="turtle"
data-content-type="text/turtle"
data-transform="updateExample"
data-options="rdfstar=true,canonicalize=true"
data-to-rdf
data-result-for="Annotating a node-compacted">
<!--
@prefix : <http://example.org/> .
:bob :age 42 .
<< :bob :age 42 >> :certainty 0.8e0 .
-->
</pre>
</aside>
</section>
<section id="advanced-concepts" class="informative">
<h2>Advanced Concepts</h2>
<p>JSON-LD allows many more sophisticated ways of describing data and
both <a>embedded nodes</a> and <a>annotation objects</a> work along with these
other features, to the extent that they are used in describing a single relationship.</p>
<section id="reverse-properties" class="informative">
<h3>Reverse Properties</h3>
<p>JSON-LD allows the description of <a data-cite="JSON-LD11#reverse-proerties"></a>
within <a>node objects</a>, either by defining a term using `@reverse`, or using
`@reverse` directly within a <a>node object</a>.</p>
<p>An <a>embedded node</a> MUST NOT, itself, use a reverse property.</p>
<p>The relationships between nodes can be reversed even when those
nodes use embedded objects:</p>
<aside class="example ds-selector-tabs"
title="Reversing relationship with embedded node">
<div class="selectors">
<button class="selected input" data-selects="compacted">Compacted (Input)</button>
<button data-selects="expanded">Expanded</button>
<button data-selects="flattened">Flattened</button>
<button data-selects="turtle">Turtle-star</button>
</div>
<pre class="compacted input selected"
data-transform="updateExample"
data-options="rdfstar=true">
<!--
{
"@context": {
"@base": "http://example.org/",
"@vocab": "http://example.org/",
"knows": {"@type": "@id"},
"claimedBy": {"@reverse": "http://example.org/claims", "@type": "@id"}
},
"@id": {
"@id": "bob",
"knows": "alice"
},
"claimedBy": "alice"
}
-->
</pre>
<pre class="expanded"
data-transform="updateExample"
data-options="rdfstar=true"
data-result-for="Reversing relationship with embedded node-compacted">
<!--
[{
"@id": {
"@id": "http://example.org/bob",
"http://example.org/knows": [{"@id": "http://example.org/alice"}]
},
"@reverse": {
"http://example.org/claims": [{"@id": "http://example.org/alice"}]
}
}]
-->
</pre>
<pre class="flattened"
data-transform="updateExample"
data-options="rdfstar=true"
data-flatten
data-result-for="Reversing relationship with embedded node-compacted">
<!--
[{
"@id": "http://example.org/alice",
"http://example.org/claims": [{
"@id": {
"@id": "http://example.org/bob",
"http://example.org/knows": [{"@id": "http://example.org/alice"}]
}
}]
}]
-->
</pre>
<pre class="turtle"
data-content-type="text/turtle"
data-transform="updateExample"
data-options="rdfstar=true"
data-to-rdf
data-result-for="Reversing relationship with embedded node-compacted">
<!--
@prefix : <http://example.org/> .
:alice :claims << :bob :knows :alice >> .
-->
</pre>
</aside>
<p>Annotations may themselves use reverse properties, in which case
the annotated triple will be the object (instead of the subject) of the annotation:</p>
<aside class="example ds-selector-tabs"
title="Reversing annotations">
<div class="selectors">
<button class="selected input" data-selects="compacted">Compacted (Input)</button>
<button data-selects="expanded">Expanded</button>
<button data-selects="flattened">Flattened</button>
<button data-selects="turtle">Turtle-star</button>
</div>
<pre class="compacted input selected"
data-transform="updateExample"
data-options="rdfstar=true">
<!--
{
"@context": {
"@base": "http://example.org/",
"@vocab": "http://example.org/",
"accordingTo": {"@type": "@id"},
"claimedBy": {"@reverse": "http://example.org/claims", "@type": "@id"}
},
"@id": "bob",
"knows": {
"@id": "alice",
"@annotation": {
"accordingTo": "alice",
"claimedBy": "bob"
}
}
}
-->
</pre>
<pre class="expanded"
data-transform="updateExample"
data-options="rdfstar=true"
data-result-for="Reversing annotations-compacted">
<!--
[{
"@id": "http://example.org/bob",
"http://example.org/knows": [{
"@id": "http://example.org/alice",
"@annotation": [{
"http://example.org/accordingTo": [{"@id": "http://example.org/alice"}],
"@reverse": {
"http://example.org/claims": [{"@id": "http://example.org/bob"}]
}
}]
}]
}]
-->
</pre>
<pre class="flattened"
data-transform="updateExample"
data-options="rdfstar=true"
data-flatten
data-result-for="Reversing annotations-compacted">
<!--
[{
"@id": "http://example.org/bob",
"http://example.org/knows": [{"@id": "http://example.org/alice"}],
"http://example.org/claims": [{
"@id": {
"@id": "http://example.org/bob",
"http://example.org/knows": [{"@id": "http://example.org/alice"}]
}
}]
}, {
"@id": {
"@id": "http://example.org/bob",
"http://example.org/knows": [{"@id": "http://example.org/alice"}]
},
"http://example.org/accordingTo": [{"@id": "http://example.org/alice"}]
}]
-->
</pre>
<pre class="turtle"
data-content-type="text/turtle"
data-transform="updateExample"
data-options="rdfstar=true"
data-to-rdf
data-result-for="Reversing annotations-compacted">
<!--
@prefix : <http://example.org/> .
:bob :knows :alice .
<< :bob :knows :alice >> :accordingTo :alice .
:bob :claims << :bob :knows :alice >> .
-->
</pre>
</aside>
</section>
<section id="deep-embedding" class="informative">
<h3>Deep Embedding</h3>
<p>[[RDFstar]] allows <a>embedded triples</a> to contain other <a>embedded triples</a>, recursively.
Similarly, an embedded node may be made up of other embedded nodes,
and annotations may be made upon embedded nodes.</p>
<aside class="example ds-selector-tabs"
title="Embedded nodes and annotations">
<div class="selectors">
<button class="selected input" data-selects="compacted">Compacted (Input)</button>
<button data-selects="expanded">Expanded</button>
<button data-selects="flattened">Flattened</button>
<button data-selects="turtle">Turtle-star</button>
</div>
<pre class="compacted input selected"
data-transform="updateExample"
data-options="rdfstar=true">
<!--
{
"@context": {
"@base": "http://example.org/",
"@vocab": "http://example.org/",
"claims": {"@type": "@id"}
},
"@id": {
"@id": "bob",
"knows": {"@id": "alice"}
},
"certainty": {
"@value": 0.8,
"@annotation": {"claims": "ted"}
}
}
-->
</pre>
<pre class="expanded"
data-transform="updateExample"
data-options="rdfstar=true"
data-result-for="Embedded nodes and annotations-compacted">
<!--
[{
"@id": {
"@id": "http://example.org/bob",
"http://example.org/knows": [{"@id": "http://example.org/alice"}]
},
"http://example.org/certainty": [{
"@value": 0.8,
"@annotation": [{
"http://example.org/claims": [{"@id": "http://example.org/ted"}]
}]
}]
}]
-->
</pre>
<pre class="flattened"
data-transform="updateExample"
data-options="rdfstar=true"
data-flatten
data-result-for="Embedded nodes and annotations-compacted">
<!--
[{
"@id": {
"@id": "http://example.org/bob",
"http://example.org/knows": [{"@id": "http://example.org/alice"}]
},
"http://example.org/certainty": [{"@value": 0.8}]
}, {
"@id": {
"@id": {
"@id": "http://example.org/bob",
"http://example.org/knows": [{"@id": "http://example.org/alice"}]
},
"http://example.org/certainty": [{"@value": 0.8}]
},
"http://example.org/claims": [{"@id": "http://example.org/ted"}]
}]
-->
</pre>
<pre class="turtle"
data-content-type="text/turtle"
data-transform="updateExample"
data-options="rdfstar=true,canonicalize=true"
data-to-rdf
data-result-for="Embedded nodes and annotations-compacted">
<!--
@prefix : <http://example.org/> .
<< :bob :knows :alice >> :certainty 0.8e0 .
<< << :bob :knows :alice >> :certainty 0.8e0 >> :claims :ted .
-->
</pre>
</aside>
</section>
<section id="mixing-annotations-and-embedded-nodes" class="informative">
<h3>Mixing Annotations and Embedded Nodes</h3>
<p><a>Annotation objects</a> and <a>embedded nodes</a> can be used together.
As well, <a>annotation objects</a> can be used to annotate <a>embedded nodes</a>
(see <a href="#deep-embedding" class="sectionRef"></a>),
<a>embedded nodes</a> may be used within <a>annotation objects</a>,
and <a>annotation objects</a> may be used to annotate annotations.
However, the <a href="#grammar-extensions">grammar</a> prevents
<a>embedded nodes</a> from including <a>annotation objects</a>.</p>
<p>While it is beyond the scope of this document to discuss use cases
for these scenarios, it is an important notion of regularity
of expression, which is shared by formats such as <a data-cite="RDFStar#turtle-star">Turtle-star</a>.</p>
<p>Consider the following examples:</p>
<aside class="example ds-selector-tabs"
title="Annotation containing embedded node">
<div class="selectors">
<button class="selected input" data-selects="compacted">Compacted (Input)</button>
<button data-selects="expanded">Expanded</button>
<button data-selects="flattened">Flattened</button>
<button data-selects="turtle">Turtle-star</button>
</div>
<pre class="compacted input selected"
data-transform="updateExample"
data-options="rdfstar=true">
<!--
{
"@context": {
"@vocab": "ex:",
"p1": {"@type": "@id"}
},
"@id": "ex:s",
"p": {
"@id": "ex:o",
"@annotation": {
"r": {
"@id": "ex:s1",
"@annotation": {
"p1": "ex:o1"
}
}
}
}
}
-->
</pre>
<pre class="expanded"
data-transform="updateExample"
data-options="rdfstar=true"
data-result-for="Annotation containing embedded node-compacted">
<!--
[{
"@id": "ex:s",
"ex:p": [{
"@id": "ex:o",
"@annotation": [{
"ex:r": [{
"@id": "ex:s1",
"@annotation": [{
"ex:p1": [{"@id": "ex:o1"}]
}]
}]
}]
}]
}]
-->
</pre>
<pre class="flattened"
data-transform="updateExample"
data-options="rdfstar=true"
data-flatten
data-result-for="Annotation containing embedded node-compacted">
<!--
[{
"@id": "ex:s",
"ex:p": [{"@id": "ex:o"}]
}, {
"@id": {
"@id": "ex:s",
"ex:p": [{"@id": "ex:o"}]
},
"ex:r": [{"@id": "ex:s1"}]
}, {
"@id": {
"@id": {
"@id": "ex:s",
"ex:p": [{"@id": "ex:o"}]
},
"ex:r": [{"@id": "ex:s1"}]
},
"ex:p1": [{"@id": "ex:o1"}]
}]
-->
</pre>
<pre class="turtle"
data-content-type="text/turtle"
data-transform="updateExample"
data-options="rdfstar=true,canonicalize=true"
data-to-rdf
data-result-for="Annotation containing embedded node-compacted">
<!--
@prefix : <ex:> .
:s :p :o {| :r :s1 {| :p1 :o1 |} |} .
-->
</pre>
</aside>
<aside class="example ds-selector-tabs"
title="Annotating an annotation">
<div class="selectors">
<button class="selected input" data-selects="compacted">Compacted (Input)</button>
<button data-selects="expanded">Expanded</button>
<button data-selects="flattened">Flattened</button>
<button data-selects="turtle">Turtle-star</button>
</div>
<pre class="compacted input selected"
data-transform="updateExample"
data-options="rdfstar=true">
<!--
{
"@context": {
"@vocab": "ex:",
"p1": {"@type": "@id"}
},
"@id": "ex:s",
"p": {
"@id": "ex:o",
"@annotation": {
"r": {
"@id": {"@id": "ex:s1", "p1": "ex:o1"}
}
}
}
}
-->
</pre>
<pre class="expanded"
data-transform="updateExample"
data-options="rdfstar=true"
data-result-for="Annotating an annotation-compacted">
<!--
[{
"@id": "ex:s",
"ex:p": [{
"@id": "ex:o",
"@annotation": [{
"ex:r": [{
"@id": {
"@id": "ex:s1",
"ex:p1": [{"@id": "ex:o1"}]
}
}]
}]
}]