Split the API portion of the JSON-LD spec into its own specification.
authorManu Sporny <msporny@digitalbazaar.com>
Sat, 15 Oct 2011 21:49:56 -0400
changeset 216 7bb900de3574
parent 215 71f9e8333bc7
child 217 4c3bafa48039
Split the API portion of the JSON-LD spec into its own specification.
spec/latest/json-ld-api/index.html
spec/latest/json-ld-api/spec.css
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spec/latest/json-ld-api/index.html	Sat Oct 15 21:49:56 2011 -0400
@@ -0,0 +1,2463 @@
+´╗┐<!DOCTYPE html>
+<html>
+<head>
+<title>The JSON-LD API 1.0</title>
+<meta http-equiv="content-type" content="text/html; charset=UTF-8">
+<!--
+  === NOTA BENE ===
+  For the three scripts below, if your spec resides on dev.w3 you can check them
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+                    // extend the bibliography entries
+                    berjon.biblio["MICRODATA"] = "Ian Hickson; et al. <a href=\"http://www.w3.org/TR/microdata/\"><cite>Microdata</cite></a> 04 March 2010. W3C Working Draft. URL: <a href=\"http://www.w3.org/TR/microdata/\">http://www.w3.org/TR/microdata/</a> ";
+                    berjon.biblio["HTML-RDFA"] = "Manu Sporny; et al. <a href=\"http://www.w3.org/TR/rdfa-in-html/\"><cite>HTML+RDFa</cite></a> 04 March 2010. W3C Working Draft. URL: <a href=\"http://www.w3.org/TR/rdfa-in-html/\">http://www.w3.org/TR/rdfa-in-html/</a> ";
+                    berjon.biblio["BCP47"] = "A. Phillips, M. Davis. <a href=\"http://tools.ietf.org/rfc/bcp/bcp47.txt\"><cite>Tags for Identifying Languages</cite></a> September 2009. IETF Best Current Practice. URL: <a href=\"http://tools.ietf.org/rfc/bcp/bcp47.txt\">http://tools.ietf.org/rfc/bcp/bcp47.txt</a>";
+                    berjon.biblio["JSON-LD"] = "Manu Sporny, Gregg Kellogg, et al. <a href=\"http://json-ld.org/spec/latest/json-ld-syntax/\"><cite>The JSON-LD Syntax</cite></a> Latest. W3C Editor's Draft. URL: <a href=\"http://json-ld.org/spec/latest/json-ld-syntax/\">http://json-ld.org/spec/latest/json-ld-syntax/</a>";
+                    berjon.biblio["RDF-API"] = "Manu Sporny, Benjamin Adrian, Nathan Rixham; et al. <a href=\"http://www.w3.org/2010/02/rdfa/sources/rdf-api/\"><cite>RDF API</cite></a> Latest. W3C Editor's Draft. URL: <a href=\"http://www.w3.org/2010/02/rdfa/sources/rdf-api/\">http://www.w3.org/2010/02/rdfa/sources/rdf-api/</a>";
+                    berjon.biblio["RDF-INTERFACES"] = "Nathan Rixham, Manu Sporny, Benjamin Adrian; et al. <a href=\"http://www.w3.org/2010/02/rdfa/sources/rdf-interfaces/\"><cite>RDF Interfaces</cite></a> Latest. W3C Editor's Draft. URL: <a href=\"http://www.w3.org/2010/02/rdfa/sources/rdf-interfaces/\">http://www.w3.org/2010/02/rdfa/sources/rdf-interfaces/</a>";
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+
+
+      var respecConfig = {
+          // specification status (e.g. WD, LCWD, NOTE, etc.). If in doubt use ED.
+          specStatus:           "unofficial",
+          //publishDate:          "2010-04-29",
+          copyrightStart:       "2010",
+
+          // the specification's short name, as in http://www.w3.org/TR/short-name/
+          shortName:            "json-ld-api",
+          subtitle:             "An Application Programming Interface for the JSON-LD Syntax",
+          // if you wish the publication date to be other than today, set this
+          // publishDate:  "2009-08-06",
+
+          // if there is a previously published draft, uncomment this and set its YYYY-MM-DD date
+          // and its maturity status
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+          ],
+
+          // editors, add as many as you like
+          // only "name" is required
+          editors:  [
+              { name: "Manu Sporny", url: "http://manu.sporny.org/",
+                company: "Digital Bazaar", companyURL: "http://digitalbazaar.com/" },
+              { name: "Gregg Kellogg", url: "http://greggkellogg.net/",
+                company: "Kellogg Associates" },
+              { name: "Dave Longley", url: "http://digitalbazaar.com/",
+                company: "Digital Bazaar", companyURL: "http://digitalbazaar.com/"}
+          ],
+
+          // authors, add as many as you like.
+          // This is optional, uncomment if you have authors as well as editors.
+          // only "name" is required. Same format as editors.
+
+          authors:  [
+              { name: "Dave Longley", url: "http://digitalbazaar.com/",
+                company: "Digital Bazaar", companyURL: "http://digitalbazaar.com/"},
+              { name: "Manu Sporny", url: "http://digitalbazaar.com/",
+                company: "Digital Bazaar", companyURL: "http://digitalbazaar.com/" },
+              { name: "Gregg Kellogg", url: "http://greggkellogg.net/",
+                company: "Kellogg Associates" },
+          ],
+
+          // name of the WG
+          wg:           "Linking Data in JSON Community Group",
+
+          // URI of the public WG page
+          wgURI:        "http://json-ld.org/",
+
+          // name (with the @w3c.org) of the public mailing to which comments are due
+          wgPublicList: "[email protected]",
+
+          // URI of the patent status for this WG, for Rec-track documents
+          // !!!! IMPORTANT !!!!
+          // This is important for Rec-track documents, do not copy a patent URI from a random
+          // document unless you know what you're doing. If in doubt ask your friendly neighbourhood
+          // Team Contact.
+          wgPatentURI:  "",
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+
+      function updateExample(doc, content) {
+        // perform transformations to make it render and prettier
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+        content = content.replace(/-->/, '');
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+      }
+
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+        content = content.replace(/!ELEMENT ([^ \t$]*)/mg, '!ELEMENT <span class="element">$1</span>');
+        return content;
+      }
+
+      function updateSchema(doc, content) {
+        // perform transformations to
+        // make it render and prettier
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+        return content;
+      }
+
+      function updateTTL(doc, content) {
+        // perform transformations to
+        // make it render and prettier
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+        content = content.replace(/@prefix/g, '<span class="sh_keyword">@prefix</span>');
+        return content;
+      }
+  </script>
+<style>
+.diff { font-weight:bold; color:#0a3; }
+ol.algorithm.update { margin-left: 2em; }
+ol.algorithm.update>li { list-style-type: none; }
+ol.algorithm.update>li>span.list-number {
+  display:block;
+  float: left;
+  margin-left: -3.5em;
+}
+</style>
+</head>
+
+<body>
+<section id="abstract">
+<p>
+JSON [[!RFC4627]] has proven to be a highly useful object serialization and
+messaging format. JSON-LD [[!JSON-LD]] harmonizes the representation of 
+Linked Data in JSON by outlining a common JSON representation format for
+expressing directed graphs; mixing both Linked Data and non-Linked Data in
+a single document. This document outlines an Application Programming
+Interface and a set of algorithms for programmatically transforming 
+JSON-LD documents.
+</p>
+</section>
+
+<section id='sotd'>
+<p>This document is an experimental work in progress.</p>
+<!-- <p>
+This document has been reviewed by W3C Members, by software
+developers, and by other W3C groups and interested parties, and is
+endorsed by the Director as a W3C Recommendation. It is a stable
+document and may be used as reference material or cited from another
+document. W3C's role in making the Recommendation is to draw attention
+to the specification and to promote its widespread deployment. This
+enhances the functionality and interoperability of the Web.
+</p> -->
+</section>
+
+<section>
+<h1>Introduction</h1>
+
+<p>
+JSON, as specified in [[!RFC4627]], is a simple language for representing
+data on the Web. Linked Data is a technique for creating a graph of interlinked data across
+different
+documents or Web sites. Data entities are described using <tref>IRI</tref>s,
+which are typically dereferencable and thus may be used to find more
+information about an entity, creating a "Web of Knowledge". JSON-LD is intended to be a simple
+publishing method for expressing not only Linked Data in JSON, but also for adding
+semantics to existing JSON.
+</p>
+
+<p>
+JSON-LD is designed as a light-weight syntax that can be used to express
+Linked Data. It is primarily intended to be a way to use Linked Data
+in Javascript and other Web-based programming environments. It is also
+useful when building interoperable Web services and when storing Linked
+Data in JSON-based document storage engines. It is practical and designed
+to be as simple as possible, utilizing the large number of JSON parsers
+and libraries available today. It is designed to be able to
+express key-value pairs, RDF data, RDFa [[RDFA-CORE]] data, Microformats
+[[MICROFORMATS]] data, and Microdata [[MICRODATA]]. That is, it supports
+every major Web-based structured data model in use today.
+</p>
+
+<p>
+The syntax does not necessarily require applications to change their JSON, but
+allows to easily add meaning by adding context in a way that is either in-band or
+out-of-band. The syntax is designed to not disturb already deployed systems
+running on JSON, but provide a smooth upgrade path from JSON to JSON with
+added semantics. Finally, the format is intended to be easy to parse, efficient to
+generate, convertible to RDF in one pass, and require a very small memory footprint
+in order to operate.
+</p>
+
+<section>
+<h2>How to Read this Document</h2>
+
+<p>
+This document is a detailed specification for a serialization of Linked
+Data in JSON. The document is primarily intended for the following audiences:
+</p>
+
+<ul>
+  <li>Authors that want a very detailed view of how JSON-LD processors 
+  operate.</li>
+  <li>Software developers that want to implement processors and APIs for
+  JSON-LD.</li>
+</ul>
+
+<p>
+To understand the basics in this specification you must first be familiar with
+JSON, which is detailed in [[!RFC4627]]. You must also understand the
+JSON-LD Syntax [[!JSON-LD]], which is the base syntax used by all of the
+algorithms in this document. To understand the API and how it is
+intended to operate  in a programming environment, it is useful to have working
+knowledge of the JavaScript programming language [[ECMA-262]] and
+WebIDL [[!WEBIDL]]. To understand how JSON-LD maps to RDF, it is helpful to be
+familiar with the basic RDF concepts [[!RDF-CONCEPTS]].</p>
+
+<p>
+  Examples may contain references to existing vocabularies and use <tref>prefix</tref>es to refer to Web Vocabularies. The following is a list of all vocabularies and their <tref>prefix</tref> abbreviations, as used in this document:
+</p>
+<ul>
+  <li>The <a href="http://purl.org/dc/terms/">Dublin Core</a>
+  vocabulary (abbreviation: <code>dc</code>, e.g., <code>dc:title</code>)</li>
+  <li>The <a href="http://xmlns.com/foaf/0.1/">Friend of a Friend</a>
+  vocabulary (abbreviation: <code>foaf</code>, e.g., <code>foaf:knows</code>)</li>
+  <li>The <a href="http://www.w3.org/1999/02/22-rdf-syntax-ns#">RDF</a>
+  vocabulary (abbreviation: <code>rdf</code>, e.g., <code>rdf:type</code>)</li>
+  <li>The <a href="http://www.w3.org/2001/XMLSchema#">XSD</a>
+  vocabulary (abbreviation: <code>xsd</code>, e.g., <code>xsd:integer</code>)</li>
+</ul>
+
+<p>
+  JSON [[RFC4627]] defines several terms which are used throughout this document:
+  <dl>
+    <dt><tdef>JSON Object</tdef></dt><dd>
+      An object structure is represented as a pair of curly brackets surrounding zero or
+      more name/value pairs (or members). A name is a <tref>string</tref>. A single colon comes after
+      each name, separating the name from the value. A single comma separates a value
+      from a following name. The names within an object SHOULD be unique.
+    </dd>
+    <dt><tdef>array</tdef></dt>
+    <dd>
+      An array is an ordered collection of values. An array structure is represented as square brackets surrounding zero or more values (or elements). Elements are separated by commas.  Within JSON-LD, array order is not preserved by default, unless
+      specific markup is provided (see <a href="#lists">Lists</a>). This is because the basic data model of JSON-LD
+      is a directed <tref>graph</tref>, which is inherently unordered.
+    </dd>
+    <dt><tdef>string</tdef></dt><dd>
+      A string is a sequence of zero or more Unicode characters, wrapped in double quotes, using backslash escapes. A
+      character is represented as a single character string.
+    </dd>
+    <dt><tdef>number</tdef></dt>
+    <dd>
+      A number is is similar to that used in most programming languages, except that the octal and hexadecimal formats are not used and that leading zeros are not allowed.</dd>
+    <dt><tdef>true</tdef> and <tdef>false</tdef></dt><dd>
+      Boolean values.
+    </dd>
+    <dt><tdef>null</tdef></dt><dd>
+      The use of the <em>null</em> value is undefined within JSON-LD.
+      <div class="issue">Supporting <em>null</em> in JSON-LD might have a number of advantages and should be evaluated. This is currently an <a href="https://github.com/json-ld/json-ld.org/issues/11">open issue</a>.</div>
+    </dd>
+  </dl>
+</p>
+</section>
+
+<section>
+<h2>Contributing</h2>
+
+<p>There are a number of ways that one may participate in the development of
+this specification:</p>
+
+<ul>
+<li>Technical discussion typically occurs on the public mailing list:
+<a href="http://lists.w3.org/Archives/Public/public-linked-json/">[email protected]</a>
+</li>
+
+<li><a href="http://json-ld.org/minutes/">Public teleconferences</a> are held
+on Tuesdays at 1500UTC on the second and fourth week of each month.
+</li>
+
+<li>Specification bugs and issues should be reported in the
+<a href="https://github.com/json-ld/json-ld.org/issues">issue tracker</a>.</li>
+
+<li><a href="https://github.com/json-ld/json-ld.org/tree/master/spec">Source code</a> for the
+specification can be found on Github.</li>
+
+<li>The <a href="http://webchat.freenode.net/?channels=#json-ld">#json-ld</a>
+IRC channel is available for real-time discussion on irc.freenode.net.</li>
+</ul>
+
+</section>
+
+</section>
+
+<section>
+<h2>The Application Programming Interface</h2>
+
+<p>This API provides a clean mechanism that enables developers to convert
+JSON-LD data into a a variety of output formats that are easier to work with in
+various programming languages. If a JSON-LD API is provided in a programming
+environment, the entirety of the following API MUST be implemented.
+</p>
+
+<section>
+<h3>JsonLdProcessor</h3>
+<dl title="[NoInterfaceObject] interface JsonLdProcessor" class="idl">
+
+  <dt>object expand()</dt>
+  <dd><a href="#expansion">Expands</a> the given <code>input</code>
+    according to the steps in the
+    <a href="#expansion-algorithm">Expansion Algorithm</a>. The
+    <code>input</code> MUST be copied, expanded and returned if there are
+    no errors. If the expansion fails, an appropriate exception MUST be thrown.
+
+    <dl class="parameters">
+     <dt>object input</dt>
+     <dd>The JSON-LD object to copy and perform the expansion upon.</dd>
+     <dt>object optional? context</dt>
+     <dd>An external context to use additionally to the context embedded in <code>input</code> when expanding the <code>input</code>.</dd>
+    </dl>
+
+    <dl class="exception" title="InvalidContext">
+     <dt>INVALID_SYNTAX</dt>
+     <dd>A general syntax error was detected in the <code>@context</code>.
+     For example, if a <code>@coerce</code> key maps to anything other than
+     a string or an array of strings, this exception would be raised.</dd>
+     <dt>MULTIPLE_DATATYPES</dt>
+     <dd>There is more than one target datatype specified for a single
+     property in the list of coercion rules. This means that the processor
+     does not know what the developer intended for the target datatype for a
+     property.</dd>
+    </dl>
+
+  </dd>
+
+  <dt>object compact()</dt>
+  <dd><a href="#compaction">Compacts</a> the given <code>input</code>
+    according to the steps in the
+    <a href="#compaction-algorithm">Compaction Algorithm</a>. The
+    <code>input</code> MUST be copied, compacted and returned if there are
+    no errors. If the compaction fails, an appropirate exception MUST be
+    thrown.
+  <dl class="parameters">
+     <dt>object input</dt>
+     <dd>The JSON-LD object to perform compaction on.</dd>
+     <dt>object optional? context</dt>
+     <dd>The base context to use when compacting the <code>input</code>.</dd>
+  </dl>
+
+    <dl class="exception" title="InvalidContext">
+     <dt>INVALID_SYNTAX</dt>
+     <dd>A general syntax error was detected in the <code>@context</code>.
+     For example, if a <code>@coerce</code> key maps to anything other than
+     a string or an array of strings, this exception would be raised.</dd>
+     <dt>MULTIPLE_DATATYPES</dt>
+     <dd>There is more than one target datatype specified for a single
+     property in the list of coercion rules. This means that the processor
+     does not know what the developer intended for the target datatype for a
+     property.</dd>
+    </dl>
+
+    <dl class="exception" title="ProcessingError">
+     <dt>LOSSY_COMPACTION</dt>
+     <dd>The compaction would lead to a loss of information, such as a
+     <code>@language</code> value.</dd>
+     <dt>CONFLICTING_DATATYPES</dt>
+     <dd>The target datatype specified in the coercion rule and the
+     datatype for the typed literal do not match.</dd>
+    </dl>
+
+  </dd>
+
+  <dt>object frame()</dt>
+  <dd><a href="#framing">Frames</a> the given <code>input</code>
+    using the <code>frame</code> according to the steps in the
+    <a href="#framing-algorithm">Framing Algorithm</a>. The
+    <code>input</code> is used to build the framed output and is returned if
+    there are no errors. If there are no matches for the frame,
+    <code>null</code> MUST be returned. Exceptions MUST be thrown if there are
+    errors.
+  <dl class="parameters">
+     <dt>object input</dt>
+     <dd>The JSON-LD object to perform framing on.</dd>
+     <dt>object frame</dt>
+     <dd>The frame to use when re-arranging the data.</dd>
+     <dt>object options</dt>
+     <dd>A set of options that will affect the framing algorithm.</dd>
+  </dl>
+
+    <dl class="exception" title="InvalidFrame">
+    <dt>INVALID_SYNTAX</dt>
+    <dd>A frame must be either an object or an array of objects, if the frame
+    is neither of these types, this exception is thrown.</dd>
+    <dt>MULTIPLE_EMBEDS</dt>
+    <dd>A subject IRI was specified in more than one place in the input
+    frame. More than one embed of a given subject IRI is not allowed, and if
+    requested, MUST result in this exception.</dd>
+    </dl>
+
+  </dd>
+
+  <dt>object normalize()</dt>
+  <dd><a href="#normalization">Normalizes</a> the given <code>input</code>
+    according to the steps in the
+    <a href="#normalization-algorithm">Normalization Algorithm</a>. The
+    <code>input</code> MUST be copied, normalized and returned if there are
+    no errors. If the compaction fails, <code>null</code> MUST be returned.
+  <dl class="parameters">
+     <dt>object input</dt>
+     <dd>The JSON-LD object to perform normalization upon.</dd>
+     <dt>object optional? context</dt>
+     <dd>An external context to use additionally to the context embedded in <code>input</code> when expanding the <code>input</code>.</dd>
+  </dl>
+
+    <dl class="exception" title="InvalidContext">
+     <dt>INVALID_SYNTAX</dt>
+     <dd>A general syntax error was detected in the <code>@context</code>.
+     For example, if a <code>@coerce</code> key maps to anything other than
+     a string or an array of strings, this exception would be raised.</dd>
+     <dt>MULTIPLE_DATATYPES</dt>
+     <dd>There is more than one target datatype specified for a single
+     property in the list of coercion rules. This means that the processor
+     does not know what the developer intended for the target datatype for a
+     property.</dd>
+    </dl>
+
+  </dd>
+
+  <dt>object triples()</dt>
+  <dd>Processes the <code>input</code> according to the
+    <a href="#rdf-conversion-algorithm">RDF Conversion Algorithm</a>, calling
+    the provided <code>tripleCallback</code> for each triple generated.
+  <dl class="parameters">
+     <dt>object input</dt>
+     <dd>The JSON-LD object to process when outputting triples.</dd>
+     <dt>JsonLdTripleCallback tripleCallback</dt>
+     <dd>A callback that is called whenever a processing error occurs on
+     the given <code>input</code>.
+     <div class="issue">This callback should be aligned with the
+       RDF API.</div></dd>
+     <dt>object optional? context</dt>
+     <dd>An external context to use additionally to the context embedded in <code>input</code> when expanding the <code>input</code>.</dd>
+  </dl>
+
+    <dl class="exception" title="InvalidContext">
+     <dt>INVALID_SYNTAX</dt>
+     <dd>A general syntax error was detected in the <code>@context</code>.
+     For example, if a <code>@coerce</code> key maps to anything other than
+     a string or an array of strings, this exception would be raised.</dd>
+     <dt>MULTIPLE_DATATYPES</dt>
+     <dd>There is more than one target datatype specified for a single
+     property in the list of coercion rules. This means that the processor
+     does not know what the developer intended for the target datatype for a
+     property.</dd>
+    </dl>
+
+  </dd>
+
+</dl>
+
+</section>
+
+<section>
+<h3>JsonLdTripleCallback</h3>
+<p>The JsonLdTripleCallback is called whenever the processor generates a
+triple during the <code>triple()</code> call.</p>
+
+<dl title="[NoInterfaceObject Callback] interface JsonLdTripleCallback"
+    class="idl">
+
+  <dt>void triple()</dt>
+  <dd>This callback is invoked whenever a triple is generated by the processor.
+  <dl class="parameters">
+     <dt>DOMString subject</dt>
+     <dd>The subject IRI that is associated with the triple.</dd>
+     <dt>DOMString property</dt>
+     <dd>The property IRI that is associated with the triple.</dd>
+     <dt>DOMString objectType</dt>
+     <dd>The type of object that is associated with the triple. Valid values
+       are <code>IRI</code> and <code>literal</code>.</dd>
+     <dt>DOMString object</dt>
+     <dd>The object value associated with the subject and the property.</dd>
+     <dt>DOMString? datatype</dt>
+     <dd>The datatype associated with the object.</dd>
+     <dt>DOMString? language</dt>
+     <dd>The language associated with the object in BCP47 format.</dd>
+  </dl>
+  </dd>
+</dl>
+</section>
+
+
+</section>
+
+<section>
+<h1>Algorithms</h1>
+
+<p>All algorithms described in this section are intended to operate on
+language-native data structures. That is, the serialization to a text-based
+JSON document isn't required as input or output to any of these algorithms and
+language-native data structures MUST be used where applicable.</p>
+
+<section>
+  <h2>Syntax Tokens and Keywords</h2>
+
+  <p>JSON-LD specifies a number of syntax tokens and keywords that are using
+  in all algorithms described in this section:</p>
+
+  <dl>
+  <dt><code>@context</code></dt><dd>Used to set the <tref>local context</tref>.</dd>
+  <dt><code>@base</code></dt><dd>Used to set the base IRI for all object IRIs affected  by the <tref>active context</tref>.</dd>
+  <dt><code>@vocab</code></dt><dd>Used to set the base IRI for all property IRIs affected by the <tref>active context</tref>.</dd>
+  <dt><code>@coerce</code></dt><dd>Used to specify type coercion rules.</dd>
+  <dt><code>@literal</code></dt><dd>Used to specify a literal value.</dd>
+  <dt><code>@iri</code></dt><dd>Used to specify an IRI value.</dd>
+  <dt><code>@language</code></dt><dd>Used to specify the language for a literal.</dd>
+  <dt><code>@datatype</code></dt><dd>Used to specify the datatype for a literal.</dd>
+  <dt><code>:</code></dt><dd>The separator for JSON keys and values that use the <tref>prefix</tref> mechanism.</dd>
+  <dt><code>@subject</code></dt><dd>Sets the active subject.</dd>
+  <dt><code>@type</code></dt><dd>Used to set the type of the active subject.</dd>
+  </dl>
+</section>
+
+<section>
+  <h2>Algorithm Terms</h2>
+  <dl>
+    <dt><tdef>initial context</tdef></dt>
+    <dd>
+      a context that is specified to the algorithm before processing begins.
+    </dd>
+    <dt><tdef>active subject</tdef></dt>
+    <dd>
+      the currently active subject that the processor should use when
+      processing.
+    </dd>
+    <dt><tdef>active property</tdef></dt>
+    <dd>
+      the currently active property that the processor should use when
+      processing.
+    </dd>
+    <dt><tdef>active object</tdef></dt>
+    <dd>
+      the currently active object that the processor should use when
+      processing.
+    </dd>
+    <dt><tdef>active context</tdef></dt>
+    <dd>
+      a context that is used to resolve <tref>prefix</tref>es and
+      <tref>term</tref>s while the processing
+      algorithm is running. The <tref>active context</tref> is the context
+      contained within the <tref>processor state</tref>.
+    </dd>
+    <dt><tdef>local context</tdef></dt>
+    <dd>
+      a context that is specified within a <tref>JSON object</tref>,
+      specified via the <code>@context</code> keyword.
+    </dd>
+    <dt><tdef>processor state</tdef></dt>
+    <dd>
+      the <tref>processor state</tref>, which includes the <tref>active
+      context</tref>, <tref>current subject</tref>, and
+      <tref>current property</tref>. The <tref>processor state</tref> is managed
+      as a stack with elements from the previous <tref>processor state</tref>
+      copied into a new <tref>processor state</tref> when entering a new
+      <tref>JSON object</tref>.
+    </dd>
+    <dt><tdef>JSON-LD input</tdef></dt>
+    <dd>
+      The JSON-LD data structure that is provided as input to the algorithm.
+    </dd>
+    <dt><tdef>JSON-LD output</tdef></dt>
+    <dd>
+      The JSON-LD data structure that is produced as output by the algorithm.
+    </dd>
+
+  </dl>
+</section>
+
+<section>
+  <h2 id="context">Context</h2>
+  <p>
+    Processing of JSON-LD data structure is managed recursively.
+    During processing, each rule is applied using information provided by the <tref>active context</tref>.
+    Processing begins by pushing a new <tref>processor state</tref> onto the <tref>processor state</tref> stack and
+    initializing the <tref>active context</tref> with the <tref>initial context</tref>. If a <tref>local context</tref> is encountered,
+    information from the <tref>local context</tref> is merged into the <tref>active context</tref>.
+  </p>
+  <p>
+    The <tref>active context</tref> is used for expanding keys and values of a <tref>JSON object</tref> (or elements
+    of a list (see <span a="#list-processing">List Processing</span>)).
+  </p>
+  <p>
+    A <tref>local context</tref> is identified within a <tref>JSON object</tref> having a key of
+    <code>@context</code> with <tref>string</tref> or a <tref>JSON object</tref> value. When processing a <tref>local
+    context</tref>, special processing rules apply:
+  </p>
+  <ol class="algorithm">
+    <li>Create a new, empty <tref>local context</tref>.</li>
+    <li>
+      If the value is a simple <tref>string</tref>, it MUST have a lexical form of IRI and used to initialize
+      a new JSON document which replaces the value for subsequent processing.
+    </li>
+    <li>If the value is a <tref>JSON object</tref>, perform the following steps:
+      <ol class="algorithm">
+        <li>
+          If the <tref>JSON object</tref> has a <code>@base</code> key, it MUST have a value of a simple
+          <tref>string</tref> with the lexical form of an absolute IRI. Add the base mapping to the <tref>local
+          context</tref>. <p class="issue">Turtle allows @base to be relative. If we did this, we
+          would have to add <a href="#iri-expansion">IRI Expansion</a>.</p>
+        </li>
+        <li>
+          If the <tref>JSON object</tref> has a <code>@vocab</code> key, it MUST have a value of a simple
+          <tref>string</tref> with the lexical form of an absolute IRI. Add the vocabulary mapping to the
+          <tref>local context</tref> after performing <a href="#iri-expansion">IRI Expansion</a> on
+          the associated value.
+        </li>
+        <li>
+          If the <tref>JSON object</tref> has a <code>@coerce</code> key, it MUST have a value of a
+          <tref>JSON object</tref>. Add the <code>@coerce</code> mapping to the <tref>local context</tref>
+          performing <a href="#iri-expansion">IRI Expansion</a> on the associated value(s).
+        </li>
+        <li>
+          Otherwise, the key MUST have the lexical form of <cite><a
+          href="http://www.w3.org/TR/2009/REC-xml-names-20091208/#NT-NCName">NCName</a></cite> and
+          MUST have the value of a simple <tref>string</tref> with the lexical form of IRI. Merge the key-value
+          pair into the <tref>local context</tref>.
+        </li>
+      </ol>
+    </li>
+    <li>
+      Merge the of <tref>local context</tref>'s <code>@coerce</code> mapping into  the
+      <tref>active context</tref>'s <code>@coerce</code> mapping as described <a href="#coerce">below</a>.
+    </li>
+    <li>
+      Merge all entries other than the <code>@coerce</code> mapping from the <tref>local context</tref> to the
+      <tref>active context</tref> overwriting any duplicate values.
+    </li>
+  </ol>
+
+  <section>
+    <h3>Coerce</h3>
+    <p>
+      Map each key-value pair in the <tref>local context</tref>'s
+      <code>@coerce</code> mapping into the <tref>active context</tref>'s
+      <code>@coerce</code> mapping, overwriting any duplicate values in
+      the <tref>active context</tref>'s <code>@coerce</code> mapping.
+      The <code>@coerce</code> mapping has either a single
+      <code>prefix:term</code> value, a single <tref>term</tref> value or an
+      <tref>array</tref> of <code>prefix:term</code> or <tref>term</tref> values.
+      When merging with an existing mapping in the <tref>active context</tref>,
+      map all <tref>prefix</tref> and <tref>term</tref> values to
+      <tref>array</tref> form and replace with the union of the value from
+      the <tref>local context</tref> and the value of the
+      <tref>active context</tref>. If the result is an <tref>array</tref>
+      with a single value, the processor MAY represent this as a string value.
+    </p>
+  </section>
+
+  <section>
+    <h3>Initial Context</h3>
+    <p>The <tref>initial context</tref> is initialized as follows:</p>
+    <ul>
+      <li>
+        <code>@base</code> is set using <cite><href="http://www.ietf.org/rfc/rfc2396.txt">section 5.1 Establishing a
+        Base URI</href="http://www.ietf.org/rfc/rfc2396.txt"></cite> of [[RFC3986]]. Processors MAY provide a means
+        of setting the base IRI programatically.
+      </li>
+      <li><code>@coerce</code> is set with a single mapping from <code>@iri</code> to <code>@type</code>.</li>
+    </ul>
+    <pre class="example" data-transform="updateExample">
+    <!--
+    {
+        "@base": ****document-location****,
+        "@coerce": {
+          "@iri": "@type"
+        }
+    }
+    -->
+    </pre>
+  </section>
+</section>
+
+<section>
+  <h2>IRI Expansion</h2>
+  <p>Keys and some values are evaluated to produce an IRI. This section defines an algorithm for
+    transforming a value representing an IRI into an actual IRI.</p>
+  <p>IRIs may be represented as an absolute IRI, a <tref>term</tref>, a <tref>prefix</tref>:<tref>term</tref> construct, or as a value relative to <code>@base</code>
+    or <code>@vocab</code>.</p>
+  <p>The algorithm for generating an IRI is:
+    <ol class="algorithm">
+      <li>Split the value into a <em>prefix</em> and <em>suffix</em> from the first occurrence of ':'.</li>
+      <li>If the prefix is a '_' (underscore), the IRI is unchanged.</li>
+      <li>If the <tref>active context</tref> contains a mapping for <em>prefix</em>, generate an IRI
+        by prepending the mapped prefix to the (possibly empty) suffix using textual concatenation. Note that an empty
+        suffix and no suffix (meaning the value contains no ':' string at all) are treated equivalently.</li>
+      <li>If the IRI being processed is for a property (i.e., a key's value in a <tref>JSON object</tref>, or a
+        value in a <code>@coerce</code> mapping) and the active context has a <code>@vocab</code> mapping,
+        join the mapped value to the suffix using textual concatenation.</li>
+      <li>If the IRI being processed is for a subject or object (i.e., not a property) and the active context has a <code>@base</code> mapping,
+        join the mapped value to the suffix using the method described in [[!RFC3986]].</li>
+      <li>Otherwise, use the value directly as an IRI.</li>
+    </ol>
+  </p>
+</section>
+
+<section>
+  <h2>IRI Compaction</h2>
+  <p>Some keys and values are expressed using IRIs. This section defines an
+    algorithm for transforming an IRI to a compact IRI using the
+    <tref>term</tref>s and <tref>prefix</tref>es specified in the
+    <tref>local context</tref>.</p>
+
+  <p>The algorithm for generating a compacted IRI is:
+    <ol class="algorithm">
+      <li>Search every key-value pair in the <tref>active context</tref> for
+        a <tref>term</tref> that is a complete match
+        against the IRI. If a complete match is found, the resulting compacted
+        IRI is the <tref>term</tref> associated with the IRI in the
+        <tref>active context</tref>.</li>
+      <li>If a complete match is not found, search for a partial match from
+        the beginning of the IRI. For all matches that are found, the resulting
+        compacted IRI is the <tref>prefix</tref> associated with the partially
+        matched IRI in the <tref>active context</tref> concatenated with a
+        colon (:) character and the unmatched part of the string. If there is
+        more than one compacted IRI produced, the final value is the
+        shortest and lexicographically least value of the entire set of compacted IRIs.</li>
+    </ol>
+  </p>
+</section>
+
+<section>
+  <h2>Value Expansion</h2>
+  <p>Some values in JSON-LD can be expressed in a compact form. These values
+    are required to be expanded at times when processing JSON-LD documents.
+  </p>
+
+  <p>The algorithm for expanding a value is:
+    <ol class="algorithm">
+      <li>If the key that is associated with the value has an associated
+        coercion entry in the <tref>local context</tref>, the resulting
+        expansion is an object populated according to the following steps:
+        <ol class="algorithm">
+          <li>If the coercion target is <code>@iri</code>, expand the value
+            by adding a new key-value pair where the key is <code>@iri</code>
+            and the value is the expanded IRI according to the
+            <a href="#iri-expansion">IRI Expansion</a> rules.</li>
+          <li>If the coercion target is a typed literal, expand the value
+            by adding two new key-value pairs. The first key-value pair
+            will be <code>@literal</code> and the unexpanded value. The second
+            key-value pair will be <code>@datatype</code> and the associated
+            coercion datatype expanded according to the
+            <a href="#iri-expansion">IRI Expansion</a> rules.</li>
+        </ol>
+      </li>
+    </ol>
+  </p>
+</section>
+
+<section>
+  <h2>Value Compaction</h2>
+  <p>Some values, such as IRIs and typed literals, may be expressed in an
+    expanded form in JSON-LD. These values are required to be compacted at
+    times when processing JSON-LD documents.
+  </p>
+
+  <p>The algorithm for compacting a value is:
+    <ol class="algorithm">
+      <li>If the <tref>local context</tref> contains a coercion target for the
+        key that is associated with the value, compact the value using the
+        following steps:
+        <ol class="algorithm">
+          <li>If the coercion target is an <code>@iri</code>, the compacted
+            value is the value associated with the <code>@iri</code> key,
+            processed according to the
+            <a href="#iri-compaction">IRI Compaction</a> steps.</li>
+          <li>If the coercion target is a typed literal, the compacted
+            value is the value associated with the <code>@literal</code> key.
+          </li>
+          <li>Otherwise, the value is not modified.</li>
+        </ol>
+      </li>
+    </ol>
+  </p>
+</section>
+
+<section>
+<h2>Expansion</h2>
+
+<p class="issue">This algorithm is a work in progress, do not implement it.</p>
+
+<p>As stated previously, expansion is the process of taking a JSON-LD
+input and expanding all IRIs and typed literals to their fully-expanded form.
+The output will not contain a single context declaration and will have all IRIs
+and typed literals fully expanded.
+</p>
+
+<section>
+<h3>Expansion Algorithm</h3>
+
+<ol class="algorithm">
+  <li>If the top-level item in the <tref>JSON-LD input</tref> is an <tref>array</tref>,
+  process each item in the <tref>array</tref> recursively using this algorithm.</li>
+  <li>If the top-level item in the <tref>JSON-LD input</tref> is an object,
+  update the <tref>local context</tref> according to the steps outlined in
+  the <a href="#context">context</a> section. Process each key, expanding
+  the key according to the <a href="#iri-expansion">IRI Expansion</a> rules.</li>
+  <ol class="algorithm">
+    <li>Process each value associated with each key:
+      <ol class="algorithm">
+        <li>If the value is an <tref>array</tref>, process each item in the <tref>array</tref>
+        recursively using this algorithm.</li>
+        <li>If the value is an object, process the object recursively
+        using this algorithm.</li>
+        <li>Otherwise, check to see the associated key has an associated
+        coercion rule. If the value should be coerced, expand the value
+        according to the <a href="#value-expansion">Value Expansion</a> rules.
+        If the value does not need to be coerced, leave the value as-is.
+        </li>
+      </ol>
+    <li>Remove the context from the object.</li>
+  </ol>
+</ol>
+</section>
+
+</section>
+
+<section>
+<h2>Compaction</h2>
+
+<p class="issue">This algorithm is a work in progress, do not implement it.</p>
+
+<p>As stated previously, compaction is the process of taking a JSON-LD
+input and compacting all IRIs using a given context. The output
+will contain a single top-level context declaration and will only use
+<tref>term</tref>s and <tref>prefix</tref>es and will ensure that all
+typed literals are fully compacted.
+</p>
+
+<section>
+<h3>Compaction Algorithm</h3>
+
+<ol class="algorithm">
+  <li>Perform the <a href="#expansion-algorithm">Expansion Algorithm</a> on
+  the <tref>JSON-LD input</tref>. This removes any existing context to allow the given context to be cleanly applied.</li>
+  <li>Set the <tref>active context</tref> to the given context.
+  <li>If the top-level item is an <tref>array</tref>, process each item in the <tref>array</tref>
+    recursively, starting at this step.
+  <li>If the top-level item is an object, compress each key using the steps
+    defined in <a href="#iri-compaction">IRI Compaction</a> and compress each
+    value using the steps defined in
+    <a href="#value-compaction">Value Compaction</a>.</li>
+  </li>
+</ol>
+</section>
+
+</section>
+
+
+<section>
+<h2>Framing</h2>
+
+<p class="issue">This algorithm is a work in progress, do not implement it.</p>
+
+<p>A JSON-LD document is a representation of a directed graph. A single
+directed graph can have many different serializations, each expressing
+exactly the same information. Developers typically don't work directly with
+graphs, but rather, prefer trees when dealing with JSON. While mapping a graph
+to a tree can be done, the layout of the end result must be specified in
+advance. This section defines an algorithm for mapping a graph to
+a tree given a <tref>frame</tref>.
+</p>
+
+<section>
+<h3>Framing Algorithm Terms</h3>
+ <dl>
+   <dt><tdef>input frame</tdef></dt>
+   <dd>
+     the initial <tref>frame</tref> provided to the framing algorithm.
+   </dd>
+   <dt><tdef>framing context</tdef></dt>
+   <dd>
+     a context containing the <tref>object embed flag</tref>, the
+     <tref>explicit inclusion flag</tref> and the
+     <tref>omit default flag</tref>.
+   </dd>
+   <dt><tdef>object embed flag</tdef></dt>
+   <dd>
+     a flag specifying that objects should be directly embedded in the output,
+     instead of being referred to by their IRI.
+   </dd>
+   <dt><tdef>explicit inclusion flag</tdef></dt>
+   <dd>
+     a flag specifying that for properties to be included in the output, they
+     must be explicitly declared in the <tref>framing context</tref>.
+   </dd>
+   <dt><tdef>omit missing properties flag</tdef></dt>
+   <dd>
+     a flag specifying that properties that are missing from the
+     <tref>JSON-LD input</tref> should be omitted from the output.
+   </dd>
+   <dt><tdef>match limit</tdef></dt>
+   <dd>
+     A value specifying the maximum number of matches to accept when building
+     arrays of values during the framing algorithm. A value of -1 specifies
+     that there is no match limit.
+   </dd>
+   <dt><tdef>map of embedded subjects</tdef></dt>
+   <dd>
+     A map that tracks if a subject has been embedded in the output of the
+     <a href="#framing-algorithm">Framing Algorithm</a>.
+   </dd>
+ </dl>
+</section>
+
+<section>
+<h3>Framing Algorithm</h3>
+
+<p>The framing algorithm takes <tref>JSON-LD input</tref> that has been
+normalized according to the
+<a href="#normalization-algorithm">Normalization Algorithm</a>
+(<strong>normalized input</strong>), an
+<tref>input frame</tref> that has been expanded according to the
+<a href="#expansion-algorithm">Expansion Algorithm</a>
+(<strong>expanded frame</strong>), and a number of options and produces
+<tref>JSON-LD output</tref>. The following series of steps is the recursive
+portion of the framing algorithm:
+</p>
+
+<ol class="algorithm">
+  <li>Initialize the <tref>framing context</tref> by setting the
+   <tref>object embed flag</tref>, clearing the
+   <tref>explicit inclusion flag</tref>, and clearing the
+   <tref>omit missing properties flag</tref>. Override these values
+   based on input options provided to the algorithm by the application.
+  </li>
+  <li>Generate a <tdef>list of frames</tdef> by processing the
+    <strong>expanded frame</strong>:
+    <ol class="algorithm">
+      <li>If the <strong>expanded frame</strong> is not an <tref>array</tref>, set
+        <tref>match limit</tref> to 1, place the
+        <strong>expanded frame</strong> into the <tref>list of frames</tref>,
+        and set the <tref>JSON-LD output</tref> to <code>null</code>.</li>
+      <li>If the <strong>expanded frame</strong> is an empty <tref>array</tref>, place an
+        empty object into the <tref>list of frames</tref>,
+        set the <tref>JSON-LD output</tref> to an <tref>array</tref>, and set
+        <tref>match limit</tref> to -1.</li>
+      <li>If the <strong>expanded frame</strong> is a non-empty <tref>array</tref>, add
+        each item in the <strong>expanded frame</strong> into the
+        <tref>list of frames</tref>, set the <tref>JSON-LD output</tref> to an
+        <tref>array</tref>, and set <tref>match limit</tref> to -1.</li>
+    </ol></li>
+  <li>Create a <tdef>match array</tdef> for each <strong>expanded frame</strong>
+    in the <tref>list of frames</tref> halting when either the
+    <tref>match limit</tref> is zero or the end of the
+    <tref>list of frames</tref> is reached. If an
+    <strong>expanded frame</strong> is
+    not an object, the processor MUST throw a <code>Invalid Frame Format</code>
+    exception. Add each matching item from the <strong>normalized input</strong>
+    to the <tref>matches array</tref> and decrement the
+    <tref>match limit</tref> by 1 if:
+    <ol class="algorithm">
+       <li>The <strong>expanded frame</strong> has an <code>rdf:type</code>
+         that exists in the item's list of <code>rdf:type</code>s. Note:
+         the <code>rdf:type</code> can be an <tref>array</tref>, but only one value needs
+         to be in common between the item and the
+         <strong>expanded frame</strong> for a match.</li>
+       <li>The <strong>expanded frame</strong> does not have an
+         <code>rdf:type</code> property, but every property in the
+         <strong>expanded frame</strong> exists in the item.</li>
+    </ol></li>
+  <li>Process each item in the <tref>match array</tref> with its associated
+    <tdef>match frame</tdef>:
+    <ol class="algorithm">
+      <li>If the <tref>match frame</tref> contains an <code>@embed</code>
+        keyword, set the <tref>object embed flag</tref> to its value.
+        If the <tref>match frame</tref> contains an <code>@explicit</code>
+        keyword, set the <tref>explicit inclusion flag</tref> to its value.
+        Note: if the keyword exists, but the value is neither
+        <code>true</code> or <code>false</code>, set the associated flag to
+        <code>true</code>.</li>
+      <li>If the <tref>object embed flag</tref> is cleared and the item has
+        the <code>@subject</code> property, replace the item with the value
+        of the <code>@subject</code> property.</li>
+      <li>If the <tref>object embed flag</tref> is set and the item has
+        the <code>@subject</code> property, and its IRI is in the
+        <tref>map of embedded subjects</tref>, throw a
+        <code>Duplicate Embed</code> exception.</li>
+      <li>If the <tref>object embed flag</tref> is set and the item has
+        the <code>@subject</code> property and its IRI is not in the
+        <tref>map of embedded subjects</tref>:
+        <ol class="algorithm">
+          <li>If the <tref>explicit inclusion flag</tref> is set,
+            then delete any key from the item that does not exist in the
+            <tref>match frame</tref>, except <code>@subject</code>.</li>
+          <li>For each key in the <tref>match frame</tref>, except for
+            keywords and <code>rdf:type</code>:
+          <ol class="algorithm">
+            <li>If the key is in the item, then build a new
+              <tdef>recursion input list</tdef> using the object or objects
+              associated with the key. If any object contains an
+              <code>@iri</code> value that exists in the
+              <tref>normalized input</tref>, replace the object in the
+              <tref>recusion input list</tref> with a new object containing
+              the <code>@subject</code> key where the value is the value of
+              the <code>@iri</code>, and all of the other key-value pairs for
+              that subject. Set the <tdef>recursion match frame</tdef> to the
+              value associated with the <tref>match frame</tref>'s key. Replace
+              the value associated with the key by recursively calling this
+              algorithm using <tref>recursion input list</tref>,
+              <tref>recursion match frame</tref> as input.</li>
+            <li>If the key is not in the item, add the key to the item and
+              set the associated value to an empty array if the
+              <tref>match frame</tref> key's value is an array
+              or <code>null</code> otherwise.</li>
+            <li>If value associated with the item's key is <code>null</code>,
+              process the <tref>omit missing properties flag</tref>:
+              <ol class="algorithm">
+                <li>If the value associated with the key in the
+                  <tref>match frame</tref> is an array, use the first frame
+                  from the array as the <tdef>property frame</tdef>, otherwise
+                  set the <tref>property frame</tref> to an empty object.</li>
+                <li>If the <tref>property frame</tref> contains an
+                <code>@omitDefault</code> keyword, set the
+                <tref>omit missing properties flag</tref> to its value.
+                Note: if the keyword exists, but the value is neither
+                <code>true</code> or <code>false</code>, set the associated
+                flag to <code>true</code>.</li>
+                <li>If the <tref>omit missing properties flag</tref> is set,
+                  delete the key in the item. Otherwise, if the
+                  <code>@default</code> keyword is set in the
+                  <tref>property frame</tref> set the item's value to the value
+                  of <code>@default</code>.</li>
+              </ol></li>
+          </ol></li>
+        </ol>
+      <li>If the <tref>JSON-LD output</tref> is <code>null</code> set it to
+        the item, otherwise, append the item to the
+        <tref>JSON-LD output</tref>.
+    </ol>
+  <li>Return the <tref>JSON-LD output</tref>.</li>
+</ol>
+
+The final, non-recursive step of the framing algorithm requires the
+<tref>JSON-LD output</tref> to be compacted according to the
+<a href="#compaction-algorithm">Compaction Algorithm</a> by using the
+context provided in the <tref>input frame</tref>. The resulting value is the
+final output of the compaction algorithm and is what should be returned to the
+application.
+
+</section>
+
+</section>
+
+<section>
+<h2>Normalization</h2>
+
+<p class="issue">This algorithm is a work in progress, do not implement it.</p>
+
+<p>Normalization is the process of taking <tref>JSON-LD input</tref> and
+performing a deterministic transformation on that input that results in all
+aspects of the graph being fully expanded and named in the
+<tref>JSON-LD output</tref>. The normalized output is generated in such a way
+that any conforming JSON-LD processor will generate identical output
+given the same input. The problem is a fairly difficult technical
+problem to solve because it requires a directed graph to be ordered into a
+set of nodes and edges in a deterministic way. This is easy to do when all of
+the nodes have unique names, but very difficult to do when some of the nodes
+are not labeled.
+</p>
+
+<p>In time, there may be more than one normalization algorithm that will need
+to be identified. For identification purposes, this algorithm is named
+"Universal Graph Normalization Algorithm 2011"
+(<abbr title="Universal Graph Normalization Algorithm 2011">UGNA2011</abbr>).
+</p>
+
+<section>
+<h3>Normalization Algorithm Terms</h3>
+ <dl>
+   <dt><tdef>label</tdef></dt>
+   <dd>
+     The subject IRI associated with a graph node. The subject IRI is expressed
+     using a key-value pair in a <tref>JSON object</tref> where the key is
+     <code>@subject</code> and the value is a string that is an IRI or
+     a <tref>JSON object</tref> containing the key <code>@iri</code> and
+     a value that is a string that is an IRI.
+   </dd>
+   <dt><tdef>list of expanded nodes</tdef></dt>
+   <dd>
+     A list of all nodes in the <tref>JSON-LD input</tref> graph containing no
+     embedded objects and having all keys and values expanded according to the
+     steps in the <a href="#expansion-algorithm">Expansion Algorithm</a>.
+   </dd>
+   <dt><tdef>alpha</tdef> and <tdef>beta</tdef> values</dt>
+   <dd>
+     The words <tref>alpha</tref> and <tref>beta</tref> refer to the first and
+     second nodes or values being examined in an algorithm. The names are
+     merely used to refer to each input value to a comparison algorithm.
+   </dd>
+   <dt><tdef>renaming counter</tdef></dt>
+   <dd>
+     A counter that is used during the
+     <a href="#node-relabeling-algorithm">Node Relabeling Algorithm</a>. The
+     counter typically starts at one (1) and counts up for every node that is
+     relabeled. There will be two such renaming counters in an implementation
+     of the normalization algorithm. The first is the
+     <tref>labeling counter</tref> and the second is the
+     <tref>deterministic labeling counter</tref>.
+   </dd>
+   <dt><tdef>serialization label</tdef></dt>
+   <dd>
+     An identifier that is created to aid in the normalization process in the
+     <a href="#deep-comparison-algorithm">Deep Comparison Algorithm</a>. The
+     value typically takes the form of <code>s&lt;NUMBER&gt;</code> or
+     <code>c&lt;NUMBER&gt;</code>.
+   </dd>
+</dl>
+</section>
+
+<section>
+<h3>Normalization State</h3>
+
+<p>When performing the steps required by the normalization algorithm,
+it is helpful to track the many pieces of information in a
+data structure called the <tdef>normalization state</tdef>. Many of these
+pieces simply provide indexes into the graph. The information
+contained in the <tref>normalization state</tref> is described below.</p>
+
+<dl>
+   <dt><tdef>node state</tdef></dt>
+   <dd>
+     Each node in the graph will be assigned a <tref>node state</tref>. This
+     state contains the information necessary to deterministically
+     <tref>label</tref> all nodes in the graph. A <tref>node state</tref>
+     includes:
+     <dl>
+        <dt><tdef>node reference</tdef></dt>
+        <dd>
+          A <tref>node reference</tref> is a reference to a node in the graph.
+          For a given <tref>node state</tref>, its <tref>node reference</tref>
+          refers to the node that the state is for. When a
+          <tref>node state</tref> is created, its <tref>node reference</tref>
+          should be to the node it is created for.
+        </dd>
+        <dt><tdef>outgoing list</tdef></dt>
+        <dd>
+          Lists the <tref>label</tref>s for all nodes that are properties of
+          the <tref>node reference</tref>. This list should be initialized
+          by iterating over every object associated with a property in the
+          <tref>node reference</tref> adding its label if it is another node.
+        </dd>
+        <dt><tdef>incoming list</tdef></dt>
+        <dd>
+          Lists the <tref>label</tref>s for all nodes in the graph for which
+          the <tref>node reference</tref> is a property. This list is
+          initialized to an empty list.
+        </dd>
+        <dt><tdef>outgoing serialization map</tdef></dt>
+        <dd>
+          Maps node <tref>label</tref>s to <tref>serialization label</tref>s.
+          This map is initialized to an empty map. When this map is populated,
+          it will be filled with keys that are the <tref>label</tref>s of every node in the
+          graph with a label that begins with <code>_:</code> and that has a
+          path, via properties, that starts with the
+          <tref>node reference</tref>.
+        </dd>
+        <dt><tdef>outgoing serialization</tdef></dt>
+        <dd>
+          A string that can be lexicographically compared to the
+          <tref>outgoing serialization</tref>s of other
+          <tref>node state</tref>s. It is a representation of the
+          <tref>outgoing serialization map</tref> and other related
+          information. This string is initialized to an empty string.
+        </dd>
+        <dt><tdef>incoming serialization map</tdef></dt>
+        <dd>
+          Maps node <tref>label</tref>s to <tref>serialization label</tref>s.
+          This map is initialized to an empty map. When this map is populated,
+          it will be filled with keys that are the <tref>label</tref>s of every
+          node in the graph with a <tref>label</tref> that begins with
+          <code>_:</code> and that has a path, via properties, that ends with
+          the <tref>node reference</tref>.
+        </dd>
+        <dt><tdef>incoming serialization</tdef></dt>
+        <dd>
+          A string that can be lexicographically compared to the
+          <tref>outgoing serialization</tref>s of other
+          <tref>node state</tref>s. It is a representation of the
+          <tref>incoming serialization map</tref> and other related
+          information. This string is initialized to an empty string.
+        </dd>
+     </dl>
+   </dd>
+   <dt><tdef>node state map</tdef></dt>
+   <dd>
+     A mapping from a node's <tref>label</tref> to a <tref>node state</tref>.
+     It is initialized to an empty map.
+   </dd>
+   <dt><tdef>labeling prefix</tdef></dt>
+   <dd>
+     The labeling prefix is a string that is used as the beginning of a node
+     <tref>label</tref>. It should be initialized to a random base string that
+     starts with the characters <code>_:</code>, is not used by any other
+     node's <tref>label</tref> in the <tref>JSON-LD input</tref>, and does not
+     start with the characters <code>_:c14n</code>. The prefix has two uses.
+     First it is used to temporarily name nodes during the normalization
+     algorithm in a way that doesn't collide with the names that already
+     exist as well as the names that will be generated by the normalization
+     algorithm. Second, it will eventually be set to <code>_:c14n</code> to
+     generate the final, deterministic labels for nodes in the graph. This
+     prefix will be concatenated with the <tref>labeling counter</tref> to
+     produce a node <tref>label</tref>. For example, <code>_:j8r3k</code> is
+     a proper initial value for the <tref>labeling prefix</tref>.
+   </dd>
+   <dt><tdef>labeling counter</tdef></dt>
+   <dd>
+     A counter that is used to label nodes. It is appended to the
+     <tref>labeling prefix</tref> to create a node <tref>label</tref>. It is
+     initialized to <code>1</code>.
+   </dd>
+   <dt><tdef>map of flattened nodes</tdef></dt>
+   <dd>
+     A map containing a representation of all nodes in the graph where the
+     key is a node <tref>label</tref> and the value is a single
+     <tref>JSON object</tref> that has no nested sub-objects
+     and has had all properties for the same node merged into a single
+     <tref>JSON object</tref>.
+   </dd>
+</dl>
+
+</section>
+
+<section>
+<h3>Normalization Algorithm</h3>
+
+<p>The normalization algorithm expands the <tref>JSON-LD input</tref>,
+flattens the data structure, and creates an initial set of names for all
+nodes in the graph. The flattened data structure is then processed by a
+node labeling algorithm in order to get a fully expanded and named list of
+nodes which is then sorted. The result is a deterministically named and
+ordered list of graph nodes.
+</p>
+
+<ol class="algorithm">
+<li>Expand the <tref>JSON-LD input</tref> according to the steps in
+the <a href="#expansion-algorithm">Expansion Algorithm</a> and store the
+result as the <strong>expanded input</strong>.</li>
+<li>Create a <tref>normalization state</tref>.</li>
+<li>Initialize the <tref>map of flattened nodes</tref> by recursively
+processing every <tdef>expanded node</tdef> in the
+<strong>expanded input</strong> in depth-first order:
+  <ol class="algorithm">
+    <li>If the <tref>expanded node</tref> is an unlabeled node, add a
+      new key-value pair to the <tref>expanded node</tref>
+      where the key is <code>@subject</code> and the value is the
+      concatenation of the <tref>labeling prefix</tref>
+      and the string value of the <tref>labeling counter</tref>.
+      Increment the <tref>labeling counter</tref>.</li>
+    <li>Add the <tref>expanded node</tref> to the
+      <tref>map of flattened nodes</tref>:
+      <ol class="algorithm">
+        <li>If the <tref>expanded node</tref>'s <tref>label</tref> is already
+          in the
+          <tref>map of flattened nodes</tref> merge all properties from the
+          entry in the <tref>map of flattened nodes</tref> into the
+          <tref>expanded node</tref>.</li>
+        <li>Go through every property associated with an array in the
+          <tref>expanded node</tref> and remove any duplicate IRI entries from
+          the array. If the resulting array only has one IRI entry, change it
+          from an array to an object.</li>
+        <li>Set the entry for the <tref>expanded node</tref>'s <tref>label</tref>
+          in the <tref>map of flattened nodes</tref> to the
+          <tref>expanded node</tref>.
+        </li></ol></li>
+    <li>After exiting the recursive step, replace the reference to the
+      <tref>expanded node</tref> with an object containing a single
+       key-value pair where the key is <code>@iri</code> and the value is
+       the value of the <code>@subject</code> key in the node.</li>
+  </ol></li>
+<li>For every entry in the <tref>map of flattened nodes</tref>, insert a
+  key-value pair into the <tref>node state map</tref> where the key is the
+  key from the <tref>map of flattened nodes</tref> and the value is a
+  <tref>node state</tref> where its <tref>node reference</tref> refers to
+  the value from the <tref>map of flattened nodes</tref>.
+<li>Populate the <tref>incoming list</tref> for each <tref>node state</tref>
+  by iterating over every node in the graph and adding its <tref>label</tref>
+  to the <tref>incoming list</tref> associated with each node found in its
+  properties.</li>
+<li>For every entry in the <tref>node state map</tref> that has a
+<tref>label</tref> that begins with <code>_:c14n</code>, relabel the node
+using the <a href="#node-relabeling-algorithm">Node Relabeling Algorithm</a>.
+<li>Label all of the nodes that contain a <code>@subject</code> key associated
+with a value starting with <code>_:</code> according to the steps in the
+<a href="#deterministic-labeling-algorithm">Deterministic Labeling Algorithm</a>.
+</li>
+</ol>
+</section>
+
+<section>
+<h4>Node Relabeling Algorithm</h4>
+
+<p>This algorithm renames a node by generating a unique
+<tdef>new label</tdef> and updating all references to that <tref>label</tref>
+in the <tref>node state map</tref>. The <tdef>old label</tdef> and the
+<tref>normalization state</tref> must be given as an input to the
+algorithm. The <tref>old label</tref> is the current <tref>label</tref> of
+the node that is to be relabeled.
+
+<p>The node relabeling algorithm is as follows:</p>
+
+<ol class="algorithm">
+  <li>If the <tref>labeling prefix</tref> is <code>_:c14n</code> and the
+    <tref>old label</tref> begins with <code>_:c14n</code> then return as
+    the node has already been renamed.
+  </li>
+  <li>Generate the <tdef>new label</tdef> by concatenating the
+    <tref>labeling prefix</tref> with the string value of the
+    <tref>labeling counter</tref>. Increment the <tref>labeling counter</tref>.
+  </li>
+  <li>For the <tref>node state</tref> associated with the
+  <tref>old label</tref>, update every node in the <tref>incoming list</tref>
+  by changing all the properties that reference the <tref>old label</tref> to
+  the <tref>new label</tref>.
+  </li>
+  <li>Change the <tref>old label</tref> key in the <tref>node state map</tref>
+    to the <tref>new label</tref> and set the associated
+    <tref>node reference</tref>'s <tref>label</tref> to the
+    <tref>new label</tref>.
+  </li>
+</ol>
+</section>
+
+<section>
+<h4>Deterministic Labeling Algorithm</h4>
+
+<p>The deterministic labeling algorithm takes the
+<tref>normalization state</tref>
+and produces a <tdef>list of finished nodes</tdef> that is sorted and
+contains deterministically named and expanded nodes from the graph.
+
+<ol class="algorithm">
+  <li>Set the <tref>labeling prefix</tref> to <code>_:c14n</code>, the
+    <tref>labeling counter</tref> to <code>1</code>,
+    the <tdef>list of finished nodes</tdef> to an empty array, and create
+    an empty array, the <tdef>list of unfinished nodes</tdef>.</li>
+  <li>For each <tref>node reference</tref> in the <tref>node state map</tref>:
+    <ol class="algorithm">
+      <li>If the node's <tref>label</tref> does not start with <code>_:</code>
+        then put the <tref>node reference</tref> in the
+        <tref>list of finished nodes</tref>.
+      </li>
+      <li>If the node's <tref>label</tref> does start with <code>_:</code>
+        then put the <tref>node reference</tref> in the
+        <tref>list of unfinished nodes</tref>.
+      </li>
+    </ol>
+  </li>
+  <li>Append to the <tref>list of finished nodes</tref> by processing
+    the remainder of the <tref>list of unfinished nodes</tref> until it is
+    empty:
+    <ol class="algorithm">
+      <li>Sort the <tref>list of unfinished nodes</tref> in descending order
+        according to the
+        <a href="#deep-comparison-algorithm">Deep Comparison Algorithm</a> to
+        determine the sort order.</li>
+      <li>Create a <tdef>list of labels</tdef> and initialize it to an
+        empty array.</li>
+      <li>For the first node from the <tref>list of unfinished nodes</tref>:
+        <ol class="algorithm">
+          <li>Add its <tref>label</tref> to the <tref>list of labels</tref>.
+          </li>
+          <li>For each key-value pair from its associated
+            <tref>outgoing serialization map</tref>, add the key to a list and
+            then sort the list according to the lexicographical order of the
+            keys' associated values. Append the list to the
+            <tref>list of nodes to label</tref>.
+          </li>
+          <li>For each key-value pair from its associated
+            <tref>incoming serialization map</tref>, add the key to a list and
+            then sort the list according to the lexicographical order of the
+            keys' associated values. Append the list to the
+            <tref>list of nodes to label</tref>.
+          </li></ol></li>
+      <li>For each <tref>label</tref> in the <tref>list of labels</tref>,
+        relabel the associated node according to the
+        <a href="#node-relabeling-algorithm">Node Relabeling Algorithm</a>. If
+        any <tref>outgoing serialization map</tref> contains a key that
+        matches the <tref>label</tref>, clear the map and set the associated
+        <tref>outgoing serialization</tref> to an empty string. If any
+        <tref>incoming serialization map</tref> contains a key that
+        matches the <tref>label</tref>, clear the map and set the associated
+        <tref>incoming serialization</tref> to an empty string.
+      </li>
+      <li>
+        Remove each node with a <tref>label</tref> that starts with
+        <code>_:c14n</code> from the <tref>list of unfinished nodes</tref> and
+        add it to the <tref>list of finished nodes</tref>.
+      </li>
+    </ol>
+  </li>
+  <li>Sort the <tref>list of finished nodes</tref> in descending order
+    according to the
+    <a href="#deep-comparison-algorithm">Deep Comparison Algorithm</a> to
+    determine the sort order.</li>
+</ol>
+</section>
+
+<section>
+<h4>Shallow Comparison Algorithm</h4>
+
+<p>
+The shallow comparison algorithm takes two unlabeled nodes,
+<tref>alpha</tref> and <tref>beta</tref>, as input and
+determines which one should come first in a sorted list. The following
+algorithm determines the steps that are executed in order to determine the
+node that should come first in a list:
+</p>
+
+<ol class="algorithm">
+  <li>Compare the total number of node properties. The node with fewer
+    properties is first.</li>
+  <li>Lexicographically sort the property IRIs for each node and compare
+    the sorted lists. If an IRI is found to be lexicographically smaller, the
+    node containing that IRI is first.</li>
+  <li>Compare the values of each property against one another:
+    <ol class="algorithm">
+      <li>The node associated with fewer property values is first.
+      </li>
+      <li>Create an <tdef>alpha list</tdef> by adding all values associated
+        with the <tref>alpha</tref> property that are not unlabeled nodes.
+      </li>
+      <li>Create a <tdef>beta list</tdef> by adding all values associated
+        with the <tref>beta</tref> property that is not an unlabeled node.
+      </li>
+      <li>Compare the length of <tref>alpha list</tref> and
+        <tref>beta list</tref>. The node associated with the list containing
+        the fewer number of items is first.</li>
+      <li>Sort <tref>alpha list</tref> and <tref>beta list</tref> according to
+        the
+        <a href="#object-comparison-algorithm">Object Comparison Algorithm</a>.
+        For each offset into the <tref>alpha list</tref>, compare the item
+        at the offset against the item at the same offset in the
+        <tref>beta list</tref> according to the
+        <a href="#object-comparison-algorithm">Object Comparison Algorithm</a>.
+        The node associated with the lesser item is first.
+    </ol></li>
+  <li>Process the <tref>incoming list</tref>s associated with each node to
+    determine order:
+    <ol class="algorithm">
+      <li>The node with the shortest <tref>incoming list</tref> is first.</li>
+      <li>Sort the <tref>incoming list</tref>s according to incoming property
+         and then incoming <tref>label</tref>.
+      <li>The node associated with the fewest number of incoming nodes is
+        first.</li>
+      <li>For each offset into the <tref>incoming list</tref>s,
+        compare the associated properties and <tref>label</tref>s:
+        <ol class="algorithm">
+          <li>The node associated with a <tref>label</tref> that does not begin with
+            <code>_:</code> is first.
+          </li>
+          <li>If the nodes' <tref>label</tref>s do not begin with
+            <code>_:</code>, then the node associated with the
+            lexicographically lesser <tref>label</tref> is first.</li>
+          </li>
+          <li>The node associated with the lexicographically lesser associated
+            property is first.
+          </li>
+          <li>The node with the <tref>label</tref> that does not begin with
+            <code>_:c14n</code> is first.
+          </li>
+          <li>The node with the lexicographically lesser <tref>label</tref>
+            is first.
+          </li>
+        </ol>
+    </ol></li>
+  <li>Otherwise, the nodes are equivalent.</li>
+</section>
+
+<section>
+<h4>Object Comparison Algorithm</h4>
+
+<p>
+The object comparison algorithm is designed to compare two graph node
+property values, <tref>alpha</tref> and <tref>beta</tref>, against the other.
+The algorithm is useful when sorting two lists of graph node properties.
+</p>
+
+<ol class="algorithm">
+  <li>If one of the values is a <tref>string</tref> and the other is not, the value that is
+    a string is first.
+  </li>
+  <li>If both values are <tref>string</tref>s, the lexicographically lesser string is
+    first.
+  </li>
+  <li>If one of the values is a literal and the other is not, the value that is
+    a literal is first.
+  </li>
+  <li>If both values are literals:
+    <ol class="algorithm">
+      <li>The lexicographically lesser string associated with
+        <code>@literal</code> is first.
+      </li>
+      <li>The lexicographically lesser string associated with
+        <code>@datatype</code> is first.
+      </li>
+      <li>The lexicographically lesser string associated with
+        <code>@language</code> is first.
+      </li>
+    </ol>
+  </li>
+  <li>If both values are expanded IRIs, the
+    lexicographically lesser string associated with <code>@iri</code>
+    is first.</li>
+  <li>Otherwise, the two values are equivalent.</li>
+</ol>
+
+</section>
+
+<section>
+<h4>Deep Comparison Algorithm</h4>
+
+<p>
+The deep comparison algorithm is used to compare the difference between two
+nodes, <tref>alpha</tref> and <tref>beta</tref>.
+A deep comparison takes the incoming and outgoing node edges in
+a graph into account if the number of properties and value of those properties
+are identical. The algorithm is helpful when sorting a list of nodes and will
+return whichever node should be placed first in a list if the two nodes are
+not truly equivalent.
+</p>
+
+<p>When performing the steps required by the deep comparison algorithm, it
+is helpful to track state information about mappings. The information
+contained in a <tref>mapping state</tref> is described below.</p>
+
+<dl class="algorithm">
+   <dt><tdef>mapping state</tdef></dt>
+   <dd>
+     <dl>
+        <dt><tdef>mapping counter</tdef></dt>
+        <dd>
+          Keeps track of the number of nodes that have been mapped to
+          <tref>serialization labels</tref>. It is initialized to
+          <code>1</code>.
+        </dd>
+        <dt><tdef>processed labels map</tdef></dt>
+        <dd>
+          Keeps track of the <tref>label</tref>s of nodes that have already
+          been assigned <tref>serialization label</tref>s. It is initialized
+          to an empty map.
+        </dd>
+        <dt><tdef>serialized labels map</tdef></dt>
+        <dd>
+          Maps a node <tref>label</tref> to its associated
+          <tref>serialization label</tref>. It is initialized to an empty map.
+        </dd>
+        <dt><tdef>adjacent info map</tdef></dt>
+        <dd>
+          Maps a <tref>serialization label</tref> to the node
+          <tref>label</tref> associated with it, the list of sorted
+          <tref>serialization label</tref>s for adjacent nodes, and the map of
+          adjacent node <tref>serialiation label</tref>s to their associated
+          node <tref>label</tref>s. It is initialized to an empty map.
+        </dd>
+        <dt><tdef>key stack</tdef></dt>
+        <dd>
+          A stack where each element contains an array of adjacent
+          <tref>serialization label</tref>s and an index into that array. It
+          is initialized to a stack containing a single element where its
+          array contains a single string element <code>s1</code> and its
+          index is set to <code>0</code>.
+        </dd>
+        <dt><tdef>serialized keys</tdef></dt>
+        <dd>
+          Keeps track of which <tref>serialization label</tref>s have already
+          been written at least once to the <tref>serialization string</tref>.
+          It is initialized to an empty map.
+        </dd>
+        <dt><tdef>serialization string</tdef></dt>
+        <dd>
+          A string that is incrementally updated as a serialization is built.
+          It is initialized to an empty string.
+        </dd>
+     </dl>
+   </dd>
+</dl>
+
+<p>The deep comparison algorithm is as follows:</p>
+
+<ol class="algorithm">
+  <li>Perform a comparison between <tref>alpha</tref> and <tref>beta</tref>
+    according to the
+    <a href="#shallow-comparison-algorithm">Shallow Comparison Algorithm</a>.
+    If the result does not show that the two nodes are equivalent, return
+    the result.
+    </li>
+  <li>Compare incoming and outgoing edges for each node, updating their
+    associated <tref>node state</tref> as each node is processed:
+    <ol class="algorithm">
+      <li>If the <tref>outgoing serialization map</tref> for <tref>alpha</tref>
+        is empty, generate the serialization according to the
+        <a href="#node-serialization-algorithm">Node Serialization Algorithm</a>.
+        Provide <tref>alpha</tref>'s <tref>node state</tref>, a new
+        <tref>mapping state</tref>,
+        <code>outgoing direction</code> to the algorithm as inputs.
+      <li>If the <tref>outgoing serialization map</tref> for <tref>beta</tref>
+        is empty, generate the serialization according to the
+        <a href="#node-serialization-algorithm">Node Serialization Algorithm</a>.
+        Provide <tref>beta</tref>'s <tref>node state</tref>, a new
+        <tref>mapping state</tref>, and
+        <code>outgoing direction</code> to the algorithm as inputs.
+      <li>If <tref>alpha</tref>'s <tref>outgoing serialization</tref> is
+        lexicographically less than <tref>beta</tref>'s, then
+        <tref>alpha</tref> is first. If it is greater, then <tref>beta</tref>
+        is first.</li>
+      <li>If the <tref>incoming serialization map</tref> for <tref>alpha</tref>
+        is empty, generate the serialization according to the
+        <a href="#node-serialization-algorithm">Node Serialization Algorithm</a>.
+        Provide <tref>alpha</tref>'s <tref>node state</tref>, a new
+        <tref>mapping state</tref> with its <tref>serialized labels map</tref>
+        set to a copy of <tref>alpha</tref>'s
+        <tref>outgoing serialization map</tref>, and
+        <code>incoming direction</code> to the algorithm as inputs.
+      <li>If the <tref>incoming serialization map</tref> for <tref>beta</tref>
+        is empty, generate the serialization according to the
+        <a href="#node-serialization-algorithm">Node Serialization Algorithm</a>.
+        Provide <tref>beta</tref>'s <tref>node state</tref>, a new
+        <tref>mapping state</tref> with its <tref>serialized labels map</tref>
+        set to a copy of <tref>beta</tref>'s
+        <tref>outgoing serialization map</tref>, and
+        <code>incoming direction</code> to the algorithm as inputs.
+      <li>If <tref>alpha</tref>'s <tref>incoming serialization</tref> is
+        lexicographically less than <tref>beta</tref>'s, then
+        <tref>alpha</tref> is first. If it is greater, then <tref>beta</tref>
+        is first.</li>
+    </ol></li>
+</ol>
+</section>
+
+<section>
+<h4>Node Serialization Algorithm</h4>
+
+<p>
+The node serialization algorithm takes a <tref>node state</tref>, a
+<tref>mapping state</tref>, and a <tdef>direction</tdef> (either
+<code>outgoing direction</code> or <code>incoming direction</code>) as
+inputs and generates a deterministic serialization for the
+<tref>node reference</tref>.
+</p>
+
+<ol class="algorithm">
+<li>If the <tref>label</tref> exists in the
+  <tref>processed labels map</tref>, terminate the algorithm as the
+  <tref>serialization label</tref> has already been created.
+</li>
+<li>Set the value associated with the <tref>label</tref> in the
+  <tref>processed labels map</tref> to <code>true</code>.
+</li>
+<li>Generate the next <tdef>serialization label</tdef> for the
+  <tref>label</tref> according to the
+  <a href="#serialization-label-generation-algorithm">Serialization Label Generation Algorithm</a>.
+</li>
+<li>Create an empty map called the <tdef>adjacent serialized labels map</tdef>
+that will store mappings from <tref>serialized label</tref>s to adjacent
+node <tref>label</tref>s.</li>
+<li>Create an empty array called the
+<tdef>adjacent unserialized labels list</tdef> that will store
+<tref>label</tref>s of adjacent nodes that haven't been assigned
+<tref>serialization label</tref>s yet.
+</li>
+<li>For every <tref>label</tref> in a list, where the list the <tref>outgoing list</tref> if
+the <tref>direction</tref> is <code>outgoing direction</code> and the
+<tref>incoming list</tref> otherwise, if the <tref>label</tref> starts with
+<code>_:</code>, it is the <tdef>target node label</tdef>:
+  <ol class="algorithm">
+    <li>Look up the <tref>target node label</tref> in the
+      <tref>processed labels map</tref> and if a mapping exists,
+      update the <tref>adjacent serialized labels map</tref> where the key is
+      the value in the <tref>serialization map</tref> and the value is the
+      <tref>target node label</tref>.</li>
+    <li>Otherwise, add the <tref>target node label</tref> to the
+      <tref>adjacent unserialized labels list</tref>.
+  </ol>
+</li>
+<li>Set the <tdef>maximum serialization combinations</tdef> to
+  <code>1</code> or the length of the
+  <tref>adjacent unserialized labels list</tref>, whichever is greater.</li>
+<li>While the <tref>maximum serialization combinations</tref> is greater than
+  <code>0</code>, perform the
+  <a href="#combinatorial-serialization-algorithm">Combinatorial Serialization Algorithm</a>
+  passing the <tref>node state</tref>, the <tref>mapping state</tref> for the
+  first iteration and a copy of it for each subsequent iteration, the
+  generated <tref>serialization label</tref>, the <tref>direction</tref>,
+  the <tref>adjacent serialized labels map</tref>, and the
+  <tref>adjacent unserialized labels list</tref>.
+  Decrement the <tref>maximum serialization combinations</tref> by
+  <code>1</code> for each iteration.
+</ol>
+
+</section>
+
+<section>
+<h4>Serialization Label Generation Algorithm</h4>
+
+<p>
+The algorithm generates a <tref>serialization label</tref> given a
+<tref>label</tref> and a <tref>mapping state</tref> and returns the
+<tref>serialization label</tref>.
+</p>
+
+ <ol class="algorithm">
+   <li>If the <tref>label</tref> is already in the
+     <tref>serialization labels map</tref>, return its associated value.
+   </li>
+   <li>If the <tref>label</tref> starts with the string <code>_:c14n</code>,
+     the <tref>serialization label</tref> is the letter <code>c</code>
+     followed by the number that follows <code>_:c14n</code> in the
+     <tref>label</tref>.
+   </li>
+   <li>Otherwise, the <tref>serialization label</tref> is the
+     letter <code>s</code> followed by the string value of
+     <tref>mapping count</tref>. Increment the <tref>mapping count</tref> by
+     <code>1</code>.
+   </li>
+   <li>Create a new key-value pair in the <tref>serialization labels map</tref>
+     where the key is the <tref>label</tref> and the value is the
+     generated <tref>serialization label</tref>.
+   </li>
+ </ol>
+</section>
+
+<section>
+<h4>Combinatorial Serialization Algorithm</h4>
+
+<p>
+The combinatorial serialization algorithm takes a <tref>node state</tref>, a
+<tref>mapping state</tref>, a <tref>serialization label</tref>, a
+<tref>direction</tref>, a <tref>adjacent serialized labels map</tref>,
+and a <tref>adjacent unserialized labels list</tref> as inputs and generates
+the lexicographically least serialization of nodes relating to the
+<tref>node reference</tref>.
+</p>
+
+<ol class="algorithm">
+  <li>If the <tref>adjacent unserialized labels list</tref> is not empty:
+    <ol class="algorithm">
+      <li>Copy the <tref>adjacent serialized labels map</tref> to the
+        <tdef>adjacent serialized labels map copy</tdef>.</li>
+      <li>Remove the first <tref>unserialized label</tref> from the
+        <tref>adjacent unserialized labels list</tref> and create a new
+        <tdef>new serialization label</tdef> according to the
+        <a href="#serialization-label-generation-algorithm">Serialization Label Generation Algorithm</a>.
+      <li>Create a new key-value mapping in the
+        <tref>adjacent serialized labels map copy</tref>
+        where the key is the <tref>new serialization label</tref> and the value
+        is the <tref>unserialized label</tref>.
+      <li>Set the <tdef>maximum serialization rotations</tdef> to
+        <code>1</code> or the length of the
+        <tref>adjacent unserialized labels list</tref>, whichever is greater.
+      </li>
+      <li>While the <tref>maximum serialization rotations</tref> is greater than
+        <code>0</code>:
+        <ol class="algorithm">
+          <li>Recursively perform the
+            <a href="#combinatorial-serialization-algorithm">Combinatorial Serialization Algorithm</a>
+            passing the <tref>mapping state</tref> for the first iteration of the
+            loop, and a copy of it for each subsequent iteration.
+          </li>
+          <li>Rotate the elements in the
+            <tref>adjacent unserialized labels list</tref> by shifting each of
+            them once to the right, moving the element at the end of the list
+            to the beginning of the list.
+          </li>
+          <li>Decrement the <tref>maximum serialization rotations</tref> by
+            <code>1</code> for each iteration.
+          </li>
+        </ol>
+      </li>
+    </ol>
+  </li>
+  <li>If the <tref>adjacent unserialized labels list</tref> is empty:
+    <ol class="algorithm">
+      <li>Create a <tdef>list of keys</tdef> from the keys in the
+        <tref>adjacent serialized labels map</tref> and sort it
+        lexicographically.
+      </li>
+      <li>Add a key-value pair to the <tref>adjacent info map</tref> where
+        the key is the <tref>serialization label</tref> and the value is
+        an object containing the <tref>node reference</tref>'s label, the
+        <tref>list of keys</tref> and the
+        <tref>adjacent serialized labels map</tref>.
+      </li>
+      <li>Update the <tref>serialization string</tref> according to the
+        <a href="#mapping-serialization-algorithm">Mapping Serialization Algorithm</a>.
+      </li>
+      <li>If the <tref>direction</tref> is <code>outgoing direction</code>
+        then <tdef>directed serialization</tdef> refers to the
+        <tref>outgoing serialization</tref> and the
+        <tdef>directed serialization map</tdef> refers to the
+        <tref>outgoing serialization map</tref>, otherwise it refers to the
+        <tref>incoming serialization</tref> and the
+        <tref>directed serialization map</tref> refers to the
+        <tref>incoming serialization map</tref>. Compare the
+        <tref>serialization string</tref> to the
+        <tref>directed serialization</tref> according to the
+        <a href="#mapping-serialization-algorithm">Serialization Comparison Algorithm</a>.
+        If the <tref>serialization string</tref> is less than or equal to
+        the <tref>directed serialization</tref>:
+        <ol class="algorithm">
+          <li>For each value in the <tref>list of keys</tref>, run the
+            <a href="#node-serialization-algorithm">Node Serialization Algorithm</a>.
+          </li>
+	       <li>Update the <tref>serialization string</tref> according to the
+	         <a href="#mapping-serialization-algorithm">Mapping Serialization Algorithm</a>.
+	       </li>
+	       <li>Compare the <tref>serialization string</tref> to the
+	         <tref>directed serialization</tref> again and if it is less than
+	         or equal and the length of the <tref>serialization string</tref> is
+	         greater than or equal to the length of the
+	         <tref>directed serialization</tref>, then set the
+	         <tref>directed serialization</tref> to the
+	         <tref>serialization string</tref> and set the
+	         <tref>directed serialization map</tref> to the
+	         <tref>serialized labels map</tref>.
+	       </li>
+        </ol>
+      </li>
+    </ol>
+  </li>
+</ol>
+
+</section>
+
+<section>
+<h4>Serialization Comparison Algorithm</h4>
+
+<p>
+The serialization comparison algorithm takes two serializations,
+<tref>alpha</tref> and <tref>beta</tref> and returns either which of the two
+is less than the other or that they are equal.
+</p>
+
+<ol class="algorithm">
+  <li>Whichever serialization is an empty string is greater. If they are
+    both empty strings, they are equal.</li>
+  <li>Return the result of a lexicographical comparison of <tref>alpha</tref>
+    and <tref>beta</tref> up to the number of characters in the shortest of
+    the two serializations.
+  </li>
+</ol>
+</section>
+
+<section>
+<h4>Mapping Serialization Algorithm</h4>
+
+<p>
+The mapping serialization algorithm incrementally updates the
+<tref>serialization string</tref> in a <tref>mapping state</tref>.
+</p>
+
+<ol class="algorithm">
+  <li>If the <tref>key stack</tref> is not empty:
+    <ol class="algorithm">
+      <li>Pop the <tdef>serialization key info</tdef> off of the
+        <tref>key stack</tref>.
+      </li>
+      <li>For each <tdef>serialization key</tdef> in the
+        <tref>serialization key info</tref> array, starting at
+        the <tdef>serialization key index</tdef> from the
+        <tref>serialization key info</tref>:
+        <ol class="algorithm">
+          <li>If the <tref>serialization key</tref> is not in the
+            <tref>adjacent info map</tref>, push the
+            <tref>serialization key info</tref> onto the
+            <tref>key stack</tref> and exit from this loop.
+          </li>
+          <li>If the <tref>serialization key</tref> is a key in
+            <tref>serialized keys</tref>, a cycle has been detected. Append
+            the concatenation of the <code>_</code> character and the
+            <tref>serialization key</tref> to the
+            <tref>serialization string</tref>.
+          <li>Otherwise, serialize all outgoing and incoming edges in the
+            related node by performing the following steps:
+            <ol class="algorithm">
+              <li>Mark the <tref>serialization key</tref> as having
+                been processed by adding a new key-value pair to
+                <tref>serialized keys</tref> where the key
+                is the <tref>serialization key</tref> and the value is
+                <code>true</code>.
+              </li>
+              <li>Set the <tdef>serialization fragment</tdef> to the value of
+                the <tref>serialization key</tref>.</li>
+              <li>Set the <tref>adjacent info</tref> to the value of the
+                <tref>serialization key</tref> in the
+                <tref>adjacent info map</tref>.
+              </li>
+              <li>Set the <tref>adjacent node label</tref> to the node
+                <tref>label</tref> from the <tref>adjacent info</tref>.
+              </li>
+              <li>If a mapping for the <tref>adjacent node label</tref>
+                exists in the <tref>map of all labels</tref>:
+                <ol class="algorithm">
+                  <li>Append the result of the
+                    <a href="">Label Serialization Algorithm</a> to the
+                    <tref>serialization fragment</tref>.
+                  </li>
+                </ol>
+              </li>
+              <li>Append all of the keys in the <tref>adjacent info</tref>
+                to the <tref>serialization fragment</tref>.
+              </li>
+              <li>Append the <tref>serialization fragment</tref> to the
+                <tref>serialization string</tref>.
+              </li>
+              <li>Push a new key info object containing the keys from the
+                <tref>adjacent info</tref> and an index of <code>0</code>
+                onto the <tref>key stack</tref>.
+              </li>
+              <li>Recursively update the <tref>serialization string</tref>
+                according to the
+                <a href="#mapping-serialization-algorithm">Mapping Serialization Algorithm</a>.
+              </li>
+            </ol>
+          </li>
+        </ol>
+      </li>
+    </ol>
+  </li>
+</ol>
+
+</section>
+
+<section>
+<h4>Label Serialization Algorithm</h4>
+
+<p>
+The label serialization algorithm serializes information about a node that
+has been assigned a particular <tref>serialization label</tref>.
+</p>
+
+<ol class="algorithm">
+  <li>Initialize the <tref>label serialization</tref> to an empty string.</li>
+  <li>Append the <code>[</code> character to the
+    <tref>label serialization</tref>.</li>
+  <li>Append all properties to the <tref>label serialization</tref> by
+    processing each key-value pair in the <tref>node reference</tref>,
+    excluding the
+    <code>@subject</code> property. The keys should be processed in
+    lexicographical order and their associated values should be processed
+    in the order produced by the
+    <a href="#object-comparison-algorithm">Object Comparison Algorithm</a>:
+    <ol class="algorithm">
+      <li>Build a string using the pattern <code>&lt;</code><strong>KEY</strong><code>&gt;</code>
+        where <strong>KEY</strong> is the current key. Append string to the
+        <tref>label serialization</tref>.</li>
+      <li>The value may be a single object or an array of objects.
+        Process all of the objects that are associated with the key, building
+        an <tdef>object string</tdef> for each item:
+        <ol class="algorithm">
+          <li>If the object contains an <code>@iri</code> key with a
+            value that starts
+            with <code>_:</code>, set the <tref>object string</tref> to
+            the value <code>_:</code>. If the value does not
+            start with <code>_:</code>, build the <tref>object string</tref>
+            using the pattern
+            <code>&lt;</code><strong>IRI</strong><code>&gt;</code>
+            where <strong>IRI</strong> is the value associated with the
+            <code>@iri</code> key.</li>
+          <li>If the object contains a <code>@literal</code> key and a
+            <code>@datatype</code> key, build the <tref>object string</tref>
+            using the pattern
+            <code>"</code><strong>LITERAL</strong><code>"^^&lt;</code><strong>DATATYPE</strong><code>&gt;</code>
+            where <strong>LITERAL</strong> is the value associated with the
+            <code>@literal</code> key and <strong>DATATYPE</strong> is the
+            value associated with the <code>@datatype</code> key.</li>
+          <li>If the object contains a <code>@literal</code> key and a
+            <code>@language</code> key, build the <tref>object string</tref>
+            using the pattern
+            <code>"</code><strong>LITERAL</strong><code>"@</code><strong>LANGUAGE</strong>
+            where <strong>LITERAL</strong> is the value associated with the
+            <code>@literal</code> key and <strong>LANGUAGE</strong> is the
+            value associated with the <code>@language</code> key.</li>
+          <li>Otherwise, the value is a string. Build the
+            <tref>object string</tref> using the pattern
+            <code>"</code><strong>LITERAL</strong><code>"</code>
+            where <strong>LITERAL</strong> is the value associated with the
+            current key.</li>
+          <li>If this is the second iteration of the loop,
+            append a <code>|</code> separator character to the
+            <tref>label serialization</tref>.</li>
+          <li>Append the <tref>object string</tref> to the
+            <tref>label serialization</tref>.</li>
+        </ol>
+    </ol>
+  </li>
+  <li>Append the <code>]</code> character to the
+    <tref>label serialization</tref>.</li>
+  <li>Append the <code>[</code> character to the
+    <tref>label serialization</tref>.</li>
+  <li>Append all incoming references for the current
+    <tref>label</tref> to the <tref>label serialization</tref> by
+    processing all of the items associated with the <tref>incoming list</tref>:
+    <ol class="algorithm">
+      <li>Build a <tdef>reference string</tdef>
+        using the pattern <code>&lt;</code><strong>PROPERTY</strong><code>&gt;</code><code>&lt;</code><strong>REFERER</strong><code>&gt;</code>
+        where <strong>PROPERTY</strong> is the property associated with the
+        incoming reference and <strong>REFERER</strong> is either the subject of
+        the node referring to the <tref>label</tref> in the incoming reference
+        or <code>_:</code> if <strong>REFERER</strong> begins with
+        <code>_:</code>.
+      <li>If this is the second iteration of the loop,
+        append a <code>|</code> separator character to the
+        <tref>label serialization</tref>.</li>
+      <li>Append the <tref>reference string</tref> to the
+        <tref>label serialization</tref>.</li>
+    </ol>
+  <li>Append the <code>]</code> character to the
+    <tref>label serialization</tref>.</li>
+  <li>Append all <tref>adjacent node labels</tref> to the
+    <tref>label serialization</tref> by concatenating the string value
+    for all of them, one after the other, to the
+    <tref>label serialization</tref>.</li>
+  <li>Push the <tref>adjacent node labels</tref> onto the
+    <tref>key stack</tref> and append the result of the
+    <a href="#mapping-serialization-algorithm">Mapping Serialization Algorithm</a>
+    to the <tref>label serialization</tref>.
+</ol>
+
+</section>
+
+</section>
+
+<section>
+
+<h3>Data Round Tripping</h3>
+
+<p>When normalizing <strong>xsd:double</strong> values, implementers MUST
+ensure that the normalized value is a string. In order to generate the
+string from a <strong>double</strong> value, output equivalent to the
+<code>printf("%1.6e", value)</code> function in C MUST be used where
+<strong>"%1.6e"</strong> is the string formatter and <strong>value</strong>
+is the value to be converted.</p>
+
+<p>To convert the a double value in JavaScript, implementers can use the
+following snippet of code:</p>
+
+<pre class="example" data-transform="updateExample">
+<!--
+// the variable 'value' below is the JavaScript native double value that is to be converted
+(value).toExponential(6).replace(/(e(?:\+|-))([0-9])$/, '$10$2')
+-->
+</pre>
+
+<p class="note">When data needs to be normalized, JSON-LD authors should
+not use values that are going to undergo automatic conversion. This is due
+to the lossy nature of <strong>xsd:double</strong> values.</p>
+
+<p class="note">Some JSON serializers, such as PHP's native implementation,
+backslash-escapes the forward slash character. For example, the value
+<code>http://example.com/</code> would be serialized as
+<code>http:\/\/example.com\/</code> in some
+versions of PHP. This is problematic when generating a byte
+stream for processes such as normalization. There is no need to
+backslash-escape forward-slashes in JSON-LD. To aid interoperability between
+JSON-LD processors, a JSON-LD serializer MUST NOT backslash-escape
+forward slashes.</p>
+
+<p class="issue">Round-tripping data can be problematic if we mix and
+match @coerce rules with JSON-native datatypes, like integers. Consider the
+following code example:</p>
+
+<pre class="example" data-transform="updateExample">
+<!--
+var myObj = { "@context" : {
+                "number" : "http://example.com/vocab#number",
+                "@coerce": {
+                   "xsd:nonNegativeInteger": "number"
+                }
+              },
+              "number" : 42 };
+
+// Map the language-native object to JSON-LD
+var jsonldText = jsonld.normalize(myObj);
+
+// Convert the normalized object back to a JavaScript object
+var myObj2 = jsonld.parse(jsonldText);
+-->
+</pre>
+
+<p class="issue">At this point, myObj2 and myObj will have different
+values for the "number" value. myObj will be the number 42, while
+myObj2 will be the string "42". This type of data round-tripping
+error can bite developers. We are currently wondering if having a
+"coerce validation" phase in the parsing/normalization phases would be a
+good idea. It would prevent data round-tripping issues like the
+one mentioned above.</p>
+
+</section>
+
+<section>
+<h2>RDF Conversion</h2>
+
+<p>A JSON-LD document MAY be converted to any other RDF-compatible document
+format using the algorithm specified in this section.</p>
+
+<p>
+  The JSON-LD Processing Model describes processing rules for extracting RDF
+  from a JSON-LD document. Note that many uses of JSON-LD may not require
+  generation of RDF.
+</p>
+
+<p>
+The processing algorithm described in this section is provided in
+order to demonstrate how one might implement a JSON-LD to RDF processor.
+Conformant implementations are only required to produce the same type and
+number of triples during the output process and are not required to
+implement the algorithm exactly as described.
+</p>
+
+<p class="issue">The RDF Conversion Algorithm is a work in progress.</p>
+
+<section class="informative">
+  <h4>Overview</h4>
+  <p>
+    JSON-LD is intended to have an easy to parse grammar that closely models existing
+    practice in using JSON for describing object representations. This allows the use
+    of existing libraries for parsing JSON.
+  </p>
+  <p>
+    As with other grammars used for describing <tref>Linked Data</tref>, a key concept is that of
+    a <em>resource</em>. Resources may be of three basic types: <em>IRI</em>s, for describing
+    externally named entities, <em>BNodes</em>, resources for which an external name does not
+    exist, or is not known, and Literals, which describe terminal entities such as strings,
+    dates and other representations having a lexical representation possibly including
+    an explicit language or datatype.
+  </p>
+  <p>
+    Data described with JSON-LD may be considered to be the representation of a graph made
+    up of <tref>subject</tref> and <tref>object</tref> resources related via a <tref>property</tref> resource.
+    However, specific implementations may choose to operate on the document as a normal
+    JSON description of objects having attributes.
+  </p>
+</section>
+
+<section>
+  <h4>RDF Conversion Algorithm Terms</h4>
+  <dl>
+    <dt><tdef>default graph</tdef></dt>
+    <dd>
+      the destination graph for all triples generated by JSON-LD markup.
+    </dd>
+  </dl>
+</section>
+
+<section>
+  <h3>RDF Conversion Algorithm</h3>
+  <p>
+    The algorithm below is designed for in-memory implementations with random access to <tref>JSON object</tref> elements.
+  </p>
+  <p>
+    A conforming JSON-LD processor implementing RDF conversion MUST implement a
+    processing algorithm that results in the same <tref>default graph</tref> that the following
+    algorithm generates:
+  </p>
+
+  <ol class="algorithm">
+    <li id="processing-step-default-context">
+      Create a new <tref>processor state</tref> with with the <tref>active context</tref> set to the
+      <tref>initial context</tref> and <tref>active subject</tref> and <tref>active property</tref>
+      initialized to NULL.
+    </li>
+
+    <li id="processing-step-associative">
+      If a <tref>JSON object</tref> is detected, perform the following steps:
+      <ol class="algorithm">
+        <li>
+          If the <tref>JSON object</tref> has a <code>@context</code> key, process the local context as
+          described in <a href="#context">Context</a>.
+        </li>
+        <li>
+          Create a new <tref>JSON object</tref> by mapping the keys from the current <tref>JSON object</tref> using the
+          <tref>active context</tref> to new keys using the associated value from the current <tref>JSON object</tref>.
+          Repeat the mapping until no entry is found within the <tref>active context</tref> for the key. Use the new
+          <tref>JSON object</tref> in subsequent steps.
+        </li>
+        <li>
+          If the <tref>JSON object</tref> has an <code>@iri</code> key, set the <tref>active object</tref> by
+          performing <a href="#iri-expansion">IRI Expansion</a> on the associated value. Generate a
+          triple representing the <tref>active subject</tref>, the <tref>active property</tref> and the
+          <tref>active object</tref>. Return the <tref>active object</tref> to the calling location.
+          <p class="issue"><code>@iri</code> really just behaves the same as <code>@subject</code>, consider consolidating them.</p>
+        </li>
+        <li>
+          If the <tref>JSON object</tref> has a <code>@literal</code> key, set the <tref>active object</tref>
+          to a literal value as follows:
+          <ol class="algorithm">
+            <li>
+              as a <tref>typed literal</tref> if the <tref>JSON object</tref> contains a <code>@datatype</code> key
+              after performing <a href="#iri-expansion">IRI Expansion</a> on the specified<code>@datatype</code>.
+            </li>
+            <li>
+              otherwise, as a <tref>plain literal</tref>. If the <tref>JSON object</tref> contains
+              a <code>@language</code> key, use it's value to set the language of the plain literal.
+            </li>
+            <li>
+              Generate a triple representing the <tref>active subject</tref>, the <tref>active property</tref> and the
+              <tref>active object</tref>. Return the <tref>active object</tref> to the calling location.
+            </li>
+          </ol>
+        </li>
+        <li id="processing-step-subject">If the <tref>JSON object</tref> has a <code>@subject</code> key:
+          <ol class="algorithm">
+            <li>
+              If the value is a <tref>string</tref>, set the <tref>active object</tref> to the result of performing
+              <a href="#iri-expansion">IRI Expansion</a>. Generate a
+              triple representing the <tref>active subject</tref>, the <tref>active property</tref> and the
+              <tref>active object</tref>. Set the <tref>active subject</tref> to the <tref>active object</tref>.
+            </li>
+            <li>
+              Create a new <tref>processor state</tref> using copies of the <tref>active context</tref>,
+              <tref>active subject</tref> and <tref>active property</tref> and process the value
+              starting at <a href="#processing-step-associative">Step 2</a>, set the <tref>active
+              subject</tref> to the result and proceed using the previous <tref>processor state</tref>.
+            </li>
+          </ol>
+        </li>
+        <li>
+          If the <tref>JSON object</tref> does not have a <code>@subject</code> key, set the <tref>active
+          object</tref> to newly generated <tdef>blank node identifier</tdef>. Generate a triple
+          representing the <tref>active subject</tref>, the <tref>active property</tref> and the
+          <tref>active object</tref>. Set the <tref>active subject</tref> to the <tref>active
+          object</tref>.
+        </li>
+        <li>
+          For each key in the <tref>JSON object</tref> that has not already been processed, perform
+          the following steps:
+          <ol class="algorithm">
+            <li>
+              If the key is <code>@type</code>, set the <tref>active property</tref>
+              to <code>rdf:type</code>.
+            </li>
+            <li>Otherwise, set the <tref>active property</tref> to the result of performing
+            <a href="#iri-expansion">IRI Expansion</a> on the key.</li>
+            <li>
+              Create a new <tref>processor state</tref> copies of the <tref>active context</tref>,
+              <tref>active subject</tref> and <tref>active property</tref> and process the value
+              starting at <a href="#processing-step-associative">Step 2</a> and proceed using the
+              previous <tref>processor state</tref>.
+            </li>
+          </ol>
+        </li>
+        <li>
+          Return the <tref>active object</tref> to the calling location.
+        </li>
+      </ol>
+    </li>
+
+    <li>
+      If a regular <tref>array</tref> is detected, process each value in the <tref>array</tref> by doing the following
+      returning the result of processing the last value in the <tref>array</tref>:
+
+      <ol class="algorithm">
+        <li>
+          Create a new <tref>processor state</tref> using copies of the <tref>active
+          context</tref>, <tref>active subject</tref> and <tref>active property</tref> and process the value
+          starting at <a href="#processing-step-associative">Step 2</a> then proceed using the previous
+          <tref>processor state</tref>.
+        </li>
+      </ol>
+    </li>
+
+    <li>
+      If a <tref>string</tref> is detected:
+      <ol class="algorithm">
+        <li>
+          If the <tref>active property</tref> is the target of a <code>@iri</code> coercion,
+          set the <tref>active object</tref> by
+          performing <a href="#iri-expansion">IRI Expansion</a> on the string.
+        </li>
+        <li>
+          Otherwise, if the <tref>active property</tref> is the target of coercion,
+          set the <tref>active object</tref> by creating a <tref>typed literal</tref> using
+          the string and the coercion key as the datatype IRI.
+        </li>
+        <li>
+          Otherwise, set the <tref>active object</tref> to a <tref>plain literal</tref> value created from
+          the string.
+        </li>
+      </ol>
+      Generate a
+      triple representing the <tref>active subject</tref>, the <tref>active property</tref> and the
+      <tref>active object</tref>.
+    </li>
+
+    <li>
+      If a <tref>number</tref> is detected, generate a <tref>typed literal</tref> using a string representation of
+      the value with datatype set to either <code>xsd:integer</code> or
+      <code>xsd:double</code>, depending on if the value contains a
+      fractional and/or an exponential component. Generate a triple using the <tref>active
+      subject</tref>, <tref>active property</tref> and the generated typed literal.
+    </li>
+
+    <li>
+      Otherwise, if <strong>true</strong> or <strong>false</strong> is detected,
+      generate a triple using the <tref>active subject</tref>, <tref>active property</tref>
+      and a <tref>typed literal</tref> value created from the string representation of the
+      value with datatype set to <code>xsd:boolean</code>.
+    </li>
+  </ol>
+</section>
+
+<section class="appendix">
+<h1>Acknowledgements</h1>
+
+<p>The editors would like to thank Mark Birbeck, who provided a great deal of
+the initial push behind the JSON-LD work via his work on RDFj,
+Dave Longley, Dave Lehn and Mike Johnson who reviewed, provided feedback, and
+performed several implementations of the specification, and Ian Davis, who
+created RDF/JSON. Thanks also to Nathan Rixham, Bradley P. Allen,
+Kingsley Idehen, Glenn McDonald, Alexandre Passant, Danny Ayers, Ted
+Thibodeau Jr., Olivier Grisel, Niklas Lindstr├Âm, Markus Lanthaler, and Richard
+Cyganiak for their input on the specification. Another huge thank you goes out
+to Dave Longley who designed many of the algorithms used in this specification,
+including the normalization algorithm which was a monumentally difficult
+design challenge.
+</p>
+</section>
+
+</body>
+</html>
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spec/latest/json-ld-api/spec.css	Sat Oct 15 21:49:56 2011 -0400
@@ -0,0 +1,4 @@
+ol.algorithm { counter-reset:numsection; list-style-type: none; }
+ol.algorithm li { margin: 0.5em 0; }
+ol.algorithm li:before { font-weight: bold; counter-increment: numsection; content: counters(numsection, ".") ") "; }
+