Update 20130822 CR draft to include the latest changes
authorMarkus Lanthaler <mark_lanthaler@gmx.net>
Tue, 20 Aug 2013 23:10:18 +0200
changeset 1908 3248128683bd
parent 1907 cbfd79099c7d
child 1909 cea8ae4b2de7
Update 20130822 CR draft to include the latest changes

So that the RDF WG can vote on it tomorrow. I didn't change anything else and also left the dates as they were. Meaning that we need to create new time stamped versions as soon as the publication is approved.

/cc @msporny @gkellogg
spec/CR/json-ld-api/20130822/diff-20130516.html
spec/CR/json-ld-api/20130822/index.html
spec/CR/json-ld/20130822/diff-20130411.html
spec/CR/json-ld/20130822/index.html
--- a/spec/CR/json-ld-api/20130822/diff-20130516.html	Tue Aug 20 22:52:51 2013 +0200
+++ b/spec/CR/json-ld-api/20130822/diff-20130516.html	Tue Aug 20 23:10:18 2013 +0200
@@ -1387,7 +1387,25 @@
 </ins></i><ins class="diff-chg">
 flag
 is
-set
+set;
+discard
+</ins><a class="tref internalDFN" title="rdf-triple" href="#dfn-rdf-triple"><ins class="diff-chg">
+triples
+</ins></a><ins class="diff-chg">
+containing
+relative
+IRIs
+and
+graphs
+with
+a
+relative
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-chg">
+IRI
+</ins></abbr><ins class="diff-chg">
+as
+graph
+name
 </ins></li><li><ins class="diff-chg">
 Update
 reference
@@ -6829,6 +6847,171 @@
 array
 </a>.
 </p>
+<div class="issue atrisk">
+<div class="issue-title" role="heading" aria-level="5">
+<span>
+<ins class="diff-new">Feature
+at
+Risk
+10
+</ins></span>:<ins class="diff-new">
+Support
+for
+@base:
+null
+</ins></div><div class="atrisk"><p class="atrisk-head"><ins class="diff-new">
+Note:
+This
+feature
+is
+</ins><a href="http://www.w3.org/2005/10/Process-20051014/tr#cfi"><ins class="diff-new">
+"at
+risk"
+</ins></a><ins class="diff-new">
+and
+may
+be
+removed
+from
+this
+specification
+based
+on
+feedback.
+Please
+send
+feedback
+to
+</ins><a href="mailto:public-rdf-comments@w3.org"><ins class="diff-new">
+public-rdf-comments@w3.org
+</ins></a>.<ins class="diff-new">
+For
+the
+current
+status
+see
+</ins><a href="http://www.w3.org/2011/rdf-wg/wiki/JSON-LD_Features_at_Risk"><ins class="diff-new">
+features
+"at
+risk"
+in
+JSON-LD
+1.0
+</ins></a></p><p><ins class="diff-new">
+Unlike
+many
+other
+serialization
+formats,
+JSON-LD
+allows
+to
+specify
+that
+there
+is
+no
+base
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr><ins class="diff-new">
+from
+within
+the
+document
+(by
+setting
+</ins><code><ins class="diff-new">
+@base
+</ins></code><ins class="diff-new">
+to
+</ins><a class="tref internalDFN" title="null" href="#dfn-null"><ins class="diff-new">
+null
+</ins></a><ins class="diff-new">
+).
+The
+result
+is
+that
+the
+algorithm
+for
+establishing
+a
+base
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr><ins class="diff-new">
+as
+specified
+in
+</ins><a href="http://tools.ietf.org/html/rfc3986#section-5.1"><ins class="diff-new">
+RFC3986
+section
+5.1
+</ins></a><ins class="diff-new">
+is
+overridden
+so
+relative
+IRIs
+remain
+relative
+IRIs
+even
+in
+the
+case
+that
+an
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr><ins class="diff-new">
+would
+be
+available
+in
+one
+of
+the
+outer
+layers
+(e.g.,
+the
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr><ins class="diff-new">
+used
+to
+retrieve
+the
+document
+or
+an
+application
+supplied
+base
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr><ins class="diff-new">
+).
+Based
+on
+implementer
+feedback,
+the
+Working
+Group
+may
+decide
+to
+remove
+this
+feature
+from
+JSON-LD
+1.0.
+</ins></p></div></div>
 <ol class="algorithm">
 <li>
 Initialize
@@ -25564,6 +25747,32 @@
 </i>:
 <ol class="algorithm">
 <li>
+<ins class="diff-new">If
+</ins><i><ins class="diff-new">
+graph
+name
+</ins></i><ins class="diff-new">
+is
+a
+</ins><a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri"><ins class="diff-new">
+relative
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr></a>,<ins class="diff-new">
+continue
+with
+the
+next
+</ins><i><ins class="diff-new">
+graph
+name
+</ins></i><ins class="diff-new">
+-
+</ins><i><ins class="diff-new">
+graph
+</ins></i><ins class="diff-new">
+pair.
+</ins></li><li>
 Initialize
 <i>
 triples
@@ -25597,6 +25806,30 @@
 </i>:
 <ol class="algorithm">
 <li>
+<ins class="diff-new">If
+</ins><i><ins class="diff-new">
+subject
+</ins></i><ins class="diff-new">
+is
+a
+</ins><a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri"><ins class="diff-new">
+relative
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr></a>,<ins class="diff-new">
+continue
+with
+the
+next
+</ins><i><ins class="diff-new">
+subject
+</ins></i><ins class="diff-new">
+-
+</ins><i><ins class="diff-new">
+node
+</ins></i><ins class="diff-new">
+pair.
+</ins></li><li>
 For
 each
 <i>
@@ -25670,7 +25903,10 @@
 keyword
 </a>
 continue
-to
+<del class="diff-old">to
+</del>
+<ins class="diff-chg">with
+</ins>
 the
 next
 <i>
@@ -25685,31 +25921,60 @@
 <li>
 Otherwise,
 <ins class="diff-new">if
-</ins><i><ins class="diff-new">
-property
-</ins></i><ins class="diff-new">
-is
-a
-</ins><a class="tref internalDFN" title="blank-node-identifier" href="#dfn-blank-node-identifier"><ins class="diff-new">
-blank
-node
-identifier
-</ins></a><ins class="diff-new">
-and
-the
-</ins><i><ins class="diff-new">
+</ins>
+<i>
+property
+</i>
+is
+<del class="diff-old">an
+</del>
+<ins class="diff-chg">a
+</ins><a class="tref internalDFN" title="blank-node-identifier" href="#dfn-blank-node-identifier"><ins class="diff-chg">
+blank
+node
+identifier
+</ins></a><ins class="diff-chg">
+and
+the
+</ins><i><ins class="diff-chg">
 produce
 generalized
 RDF
-</ins></i><ins class="diff-new">
+</ins></i><ins class="diff-chg">
 flag
 is
 not
-</ins><a class="tref internalDFN" title="true" href="#dfn-true"><ins class="diff-new">
-true
-</ins></a>,<ins class="diff-new">
+</ins><a class="tref internalDFN" title="true" href="#dfn-true"><ins class="diff-chg">
+true
+</ins></a>,<ins class="diff-chg">
 continue
-to
+with
+the
+next
+</ins><i><ins class="diff-chg">
+property
+</ins></i><ins class="diff-chg">
+-
+</ins><i><ins class="diff-chg">
+values
+</ins></i><ins class="diff-chg">
+pair.
+</ins></li><li><ins class="diff-chg">
+Otherwise,
+if
+</ins><i><ins class="diff-chg">
+property
+</ins></i><ins class="diff-chg">
+is
+a
+</ins><a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri"><ins class="diff-chg">
+relative
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-chg">
+IRI
+</ins></abbr>
+</a>,
+<ins class="diff-new">continue
+with
 the
 next
 </ins><i><ins class="diff-new">
@@ -25722,13 +25987,14 @@
 pair.
 </ins></li><li><ins class="diff-new">
 Otherwise,
-</ins>
-<i>
-property
-</i>
-is
-an
-<a class="tref internalDFN" title="iri" href="#dfn-iri">
+</ins><i><ins class="diff-new">
+property
+</ins></i><ins class="diff-new">
+is
+an
+</ins><a class="tref internalDFN" title="absolute-iri" href="#dfn-absolute-iri"><ins class="diff-new">
+absolute
+</ins>
 <abbr title="Internationalized Resource Identifier">
 IRI
 </abbr>
@@ -25895,7 +26161,29 @@
 to
 <i>
 triples
-</i>.
+<del class="diff-old">.
+</del>
+</i>,
+<ins class="diff-chg">unless
+the
+result
+is
+</ins><a class="tref internalDFN" title="null" href="#dfn-null"><ins class="diff-chg">
+null
+</ins></a>,<ins class="diff-chg">
+indicating
+a
+</ins><a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri"><ins class="diff-chg">
+relative
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-chg">
+IRI
+</ins></abbr></a><ins class="diff-chg">
+that
+has
+to
+be
+ignored.
+</ins>
 </li>
 </ol>
 </li>
@@ -26010,6 +26298,42 @@
 RDF
 triple
 </a>.
+<ins class="diff-new">If
+a
+</ins><a class="tref internalDFN" title="node-object" href="#dfn-node-object"><ins class="diff-new">
+node
+object
+</ins></a><ins class="diff-new">
+containing
+a
+</ins><a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri"><ins class="diff-new">
+relative
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr></a><ins class="diff-new">
+is
+passed
+to
+the
+algorithm,
+</ins><a class="tref internalDFN" title="null" href="#dfn-null"><ins class="diff-new">
+null
+</ins></a><ins class="diff-new">
+is
+returned
+which
+then
+causes
+the
+resulting
+</ins><a class="tref internalDFN" title="rdf-triple" href="#dfn-rdf-triple"><ins class="diff-new">
+RDF
+triple
+</ins></a><ins class="diff-new">
+to
+be
+ignored.
+</ins>
 </p>
 <section class="informative">
 <h4 id="overview-14">
@@ -26055,12 +26379,18 @@
 to
 <a class="tref internalDFN" title="iri" href="#dfn-iri">
 IRIs
-</a>
-or
+<del class="diff-old">or
+</del>
+</a>,
 <a class="tref internalDFN" title="blank-node-identifier" href="#dfn-blank-node-identifier">
 blank
 node
 identifiers
+</a>,
+<ins class="diff-new">or
+</ins><a class="tref internalDFN" title="null" href="#dfn-null"><ins class="diff-new">
+null
+</ins>
 </a>.
 </p>
 </section>
@@ -26106,6 +26436,36 @@
 node
 object
 </a>
+<ins class="diff-new">and
+the
+value
+of
+its
+</ins><code><ins class="diff-new">
+@id
+</ins></code><ins class="diff-new">
+member
+is
+a
+</ins><a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri"><ins class="diff-new">
+relative
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr></a>,<ins class="diff-new">
+return
+</ins><a class="tref internalDFN" title="null" href="#dfn-null"><ins class="diff-new">
+null
+</ins></a>.</li><li><ins class="diff-new">
+If
+</ins><i><ins class="diff-new">
+item
+</ins></i><ins class="diff-new">
+is
+a
+</ins><a class="tref internalDFN" title="node-object" href="#dfn-node-object"><ins class="diff-new">
+node
+object
+</ins></a>,
 return
 the
 <a class="tref internalDFN" title="iri" href="#dfn-iri">
@@ -26656,6 +27016,26 @@
 </a>
 is
 empty.
+<ins class="diff-new">If
+a
+list
+element
+represents
+a
+</ins><a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri"><ins class="diff-new">
+relative
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-new">
+IRI
+</ins></abbr></a>,<ins class="diff-new">
+the
+corresponding
+</ins><code><ins class="diff-new">
+rdf:first
+</ins></code><ins class="diff-new">
+triple
+is
+omitted.
+</ins>
 </p>
 </section>
 <section>
@@ -26769,25 +27149,33 @@
 </i>:
 <ol class="algorithm">
 <li>
-Append
-a
-<a class="tref internalDFN" title="triple" href="http://www.w3.org/TR/rdf11-concepts/#dfn-rdf-triple">
+<del class="diff-old">Append
+a
 triple
-</a>
 composed
 of
-<i>
-subject
-</i>,
-<code>
+</del>
+<ins class="diff-chg">Initialize
+</ins>
+<i>
+<del class="diff-old">subject
+,
 rdf:first
-</code>,
-and
-the
-result
-of
-using
-th
+,
+and
+</del>
+<ins class="diff-chg">object
+</ins></i><ins class="diff-chg">
+to
+</ins>
+the
+result
+of
+using
+<del class="diff-old">th
+</del>
+<ins class="diff-chg">the
+</ins>
 <a href="#object-to-rdf-conversion">
 Object
 to
@@ -26806,6 +27194,30 @@
 </i>.
 </li>
 <li>
+<ins class="diff-new">Unless
+</ins><i><ins class="diff-new">
+object
+</ins></i><ins class="diff-new">
+is
+</ins><a class="tref internalDFN" title="null" href="#dfn-null"><ins class="diff-new">
+null
+</ins></a>,<ins class="diff-new">
+append
+a
+</ins><a class="tref internalDFN" title="triple" href="http://www.w3.org/TR/rdf11-concepts/#dfn-rdf-triple"><ins class="diff-new">
+triple
+</ins></a><ins class="diff-new">
+composed
+of
+</ins><i><ins class="diff-new">
+subject
+</ins></i>,<code><ins class="diff-new">
+rdf:first
+</ins></code>,<ins class="diff-new">
+and
+</ins><i><ins class="diff-new">
+object
+</ins></i>.</li><li>
 Set
 <i>
 rest
--- a/spec/CR/json-ld-api/20130822/index.html	Tue Aug 20 22:52:51 2013 +0200
+++ b/spec/CR/json-ld-api/20130822/index.html	Tue Aug 20 23:10:18 2013 +0200
@@ -580,7 +580,8 @@
     <li>Clarify that blank node identifier are supported as value of <code>@vocab</code></li>
     <li>When generating RDF, exclude <a class="tref internalDFN" title="rdf-triple" href="#dfn-rdf-triple">triples</a> containing a
       <a class="tref internalDFN" title="blank-node" href="#dfn-blank-node">blank node</a> <a class="tref internalDFN" title="rdf-predicate" href="#dfn-rdf-predicate">predicate</a>, unless the
-      <i>produce generalized RDF</i> flag is set</li>
+      <i>produce generalized RDF</i> flag is set; discard <a class="tref internalDFN" title="rdf-triple" href="#dfn-rdf-triple">triples</a>
+      containing relative IRIs and graphs with a relative <abbr title="Internationalized Resource Identifier">IRI</abbr> as graph name</li>
     <li>Update reference to DOM Promises (have been called DOM Futures)</li>
     <li>Fix bug in <a href="#serialize-rdf-as-json-ld-algorithm">Serialize RDF to JSON-LD algorithm</a> to
       handle lists correctly</li>
@@ -1275,6 +1276,23 @@
         If <i>remote contexts</i> is not passed, it is initialized to an empty
         <a class="tref internalDFN" title="array" href="#dfn-array">array</a>.</p>
 
+      <div class="issue atrisk"><div class="issue-title" role="heading" aria-level="5"><span>Feature at Risk 10</span>: Support for @base: null </div><div class="atrisk">
+        <p class="atrisk-head">Note: This feature is
+          <a href="http://www.w3.org/2005/10/Process-20051014/tr#cfi">"at risk"</a> and may
+          be removed from this specification based on feedback. Please send feedback to
+          <a href="mailto:public-rdf-comments@w3.org">public-rdf-comments@w3.org</a>.
+          For the current status see
+          <a href="http://www.w3.org/2011/rdf-wg/wiki/JSON-LD_Features_at_Risk">features "at risk" in JSON-LD 1.0</a></p>
+       <p>Unlike many other serialization formats, JSON-LD allows to specify that
+        there is no base <abbr title="Internationalized Resource Identifier">IRI</abbr> from within the document (by setting <code>@base</code> to
+        <a class="tref internalDFN" title="null" href="#dfn-null">null</a>). The result is that the algorithm for establishing a base <abbr title="Internationalized Resource Identifier">IRI</abbr>
+        as specified in <a href="http://tools.ietf.org/html/rfc3986#section-5.1">RFC3986 section 5.1</a>
+        is overridden so relative IRIs remain relative IRIs even in the case that an <abbr title="Internationalized Resource Identifier">IRI</abbr>
+        would be available in one of the outer layers (e.g., the <abbr title="Internationalized Resource Identifier">IRI</abbr> used to retrieve
+        the document or an application supplied base <abbr title="Internationalized Resource Identifier">IRI</abbr>). Based on implementer feedback,
+        the Working Group may decide to remove this feature from JSON-LD 1.0.</p>
+      </div></div>
+
       <ol class="algorithm">
         <li>Initialize <i>result</i> to the result of cloning
           <a class="tref internalDFN" title="active-context" href="#dfn-active-context">active context</a>.</li>
@@ -3562,10 +3580,14 @@
         <li>For each <i>graph name</i> and <i>graph</i> in <i>node map</i>
           ordered by <i>graph name</i>:
           <ol class="algorithm">
+            <li>If <i>graph name</i> is a <a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri">relative <abbr title="Internationalized Resource Identifier">IRI</abbr></a>, continue
+              with the next <i>graph name</i>-<i>graph</i> pair.</li>
             <li>Initialize <i>triples</i> as an empty <a class="tref internalDFN" title="array" href="#dfn-array">array</a>.</li>
             <li>For each <i>subject</i> and <i>node</i> in <i>graph</i> ordered
               by <i>subject</i>:
               <ol class="algorithm">
+                <li>If <i>subject</i> is a <a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri">relative <abbr title="Internationalized Resource Identifier">IRI</abbr></a>, continue
+                  with the next <i>subject</i>-<i>node</i> pair.</li>
                 <li>For each <i>property</i> and <i>values</i> in <i>node</i>
                   ordered by <i>property</i>:
                   <ol class="algorithm">
@@ -3574,11 +3596,13 @@
                       composed of <i>subject</i>, <code>rdf:type</code>,
                       and <i>type</i> to <i>triples</i>.</li>
                     <li>Otherwise, if <i>property</i> is a <a class="tref internalDFN" title="keyword" href="#dfn-keyword">keyword</a>
-                      continue to the next <i>property</i>-<i>values</i> pair.</li>
+                      continue with the next <i>property</i>-<i>values</i> pair.</li>
                     <li>Otherwise, if <i>property</i> is a <a class="tref internalDFN" title="blank-node-identifier" href="#dfn-blank-node-identifier">blank node identifier</a> and
                       the <i>produce generalized RDF</i> flag is not <a class="tref internalDFN" title="true" href="#dfn-true">true</a>,
-                      continue to the next <i>property</i>-<i>values</i> pair.</li>
-                    <li>Otherwise, <i>property</i> is an <a class="tref internalDFN" title="iri" href="#dfn-iri"><abbr title="Internationalized Resource Identifier">IRI</abbr></a> or
+                      continue with the next <i>property</i>-<i>values</i> pair.</li>
+                    <li>Otherwise, if <i>property</i> is a <a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri">relative <abbr title="Internationalized Resource Identifier">IRI</abbr></a>,
+                      continue with the next <i>property</i>-<i>values</i> pair.</li>
+                    <li>Otherwise, <i>property</i> is an <a class="tref internalDFN" title="absolute-iri" href="#dfn-absolute-iri">absolute <abbr title="Internationalized Resource Identifier">IRI</abbr></a> or
                       <a class="tref internalDFN" title="blank-node-identifier" href="#dfn-blank-node-identifier">blank node identifier</a>. For each <i>item</i>
                       in <i>values</i>:
                       <ol class="algorithm">
@@ -3596,7 +3620,9 @@
                           composed of <i>subject</i>, <i>property</i>, and
                           the result of using the
                           <a href="#object-to-rdf-conversion">Object to RDF Conversion algorithm</a>
-                          passing <i>item</i> to <i>triples</i>.</li>
+                          passing <i>item</i> to <i>triples</i>, unless the result is
+                          <a class="tref internalDFN" title="null" href="#dfn-null">null</a>, indicating a <a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri">relative <abbr title="Internationalized Resource Identifier">IRI</abbr></a> that has
+                          to be ignored.</li>
                       </ol>
                     </li>
                   </ol>
@@ -3620,7 +3646,10 @@
     <p>This algorithm takes a <a class="tref internalDFN" title="node-object" href="#dfn-node-object">node object</a> or <a class="tref internalDFN" title="value-object" href="#dfn-value-object">value object</a>
       and transforms it into an
       <a class="tref externalDFN" title="rdf-resource" href="http://www.w3.org/TR/rdf11-concepts/#dfn-resource">RDF resource</a>
-      to be used as the <a class="tref internalDFN" title="object" href="http://www.w3.org/TR/rdf11-concepts/#dfn-object">object</a> of an <a class="tref internalDFN" title="rdf-triple" href="#dfn-rdf-triple">RDF triple</a>.</p>
+      to be used as the <a class="tref internalDFN" title="object" href="http://www.w3.org/TR/rdf11-concepts/#dfn-object">object</a> of an <a class="tref internalDFN" title="rdf-triple" href="#dfn-rdf-triple">RDF triple</a>. If a
+      <a class="tref internalDFN" title="node-object" href="#dfn-node-object">node object</a> containing a <a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri">relative <abbr title="Internationalized Resource Identifier">IRI</abbr></a> is passed to
+      the algorithm, <a class="tref internalDFN" title="null" href="#dfn-null">null</a> is returned which then causes the resulting
+      <a class="tref internalDFN" title="rdf-triple" href="#dfn-rdf-triple">RDF triple</a> to be ignored.</p>
 
     <section class="informative">
       <h4 id="overview-14">Overview</h4><p><em>This section is non-normative.</em></p>
@@ -3629,8 +3658,9 @@
         <a class="tref internalDFN" title="rdf-literal" href="http://www.w3.org/TR/rdf11-concepts/#dfn-literal">RDF literals</a> as described in
         <a class="sectionRef" href="#data-round-tripping">section 10.6 Data Round Tripping</a>
         whereas <a class="tref internalDFN" title="node-object" href="#dfn-node-object">node objects</a> are transformed
-        to <a class="tref internalDFN" title="iri" href="#dfn-iri">IRIs</a> or
-        <a class="tref internalDFN" title="blank-node-identifier" href="#dfn-blank-node-identifier">blank node identifiers</a>.</p>
+        to <a class="tref internalDFN" title="iri" href="#dfn-iri">IRIs</a>,
+        <a class="tref internalDFN" title="blank-node-identifier" href="#dfn-blank-node-identifier">blank node identifiers</a>,
+        or <a class="tref internalDFN" title="null" href="#dfn-null">null</a>.</p>
     </section>
 
     <section>
@@ -3640,7 +3670,10 @@
         either a <a class="tref internalDFN" title="value-object" href="#dfn-value-object">value object</a> or <a class="tref internalDFN" title="node-object" href="#dfn-node-object">node object</a>.</p>
 
       <ol class="algorithm">
-        <li>If <i>item</i> is a <a class="tref internalDFN" title="node-object" href="#dfn-node-object">node object</a> return the
+        <li>If <i>item</i> is a <a class="tref internalDFN" title="node-object" href="#dfn-node-object">node object</a> and the value of
+          its <code>@id</code> member is a <a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri">relative <abbr title="Internationalized Resource Identifier">IRI</abbr></a>, return
+          <a class="tref internalDFN" title="null" href="#dfn-null">null</a>.</li>
+        <li>If <i>item</i> is a <a class="tref internalDFN" title="node-object" href="#dfn-node-object">node object</a>, return the
           <a class="tref internalDFN" title="iri" href="#dfn-iri"><abbr title="Internationalized Resource Identifier">IRI</abbr></a> or <a class="tref internalDFN" title="blank-node-identifier" href="#dfn-blank-node-identifier">blank node identifier</a> associated
           with its <code>@id</code> member.</li>
         <li>Otherwise, <i>item</i> is a <a class="tref internalDFN" title="value-object" href="#dfn-value-object">value object</a>. Initialize
@@ -3704,7 +3737,8 @@
         <code>rdf:rest</code> <a class="tref internalDFN" title="rdf-triple" href="#dfn-rdf-triple">triples</a>. The
         algorithm returns the list head, which is either the first allocated
         <a class="tref internalDFN" title="blank-node-identifier" href="#dfn-blank-node-identifier">blank node identifier</a> or <code>rdf:nil</code> if the
-        <a class="tref internalDFN" title="list" href="#dfn-list">list</a> is empty.</p>
+        <a class="tref internalDFN" title="list" href="#dfn-list">list</a> is empty. If a list element represents a <a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri">relative <abbr title="Internationalized Resource Identifier">IRI</abbr></a>,
+        the corresponding <code>rdf:first</code> triple is omitted.</p>
     </section>
 
     <section>
@@ -3722,10 +3756,11 @@
         <li>Initialize an empty <a class="tref internalDFN" title="array" href="#dfn-array">array</a> <i>list triples</i>.</li>
         <li>For each pair of <i>subject</i> from <i>bnodes</i> and <i>item</i> from <i>list</i>:
           <ol class="algorithm">
-            <li>Append a <a class="tref internalDFN" title="triple" href="http://www.w3.org/TR/rdf11-concepts/#dfn-rdf-triple">triple</a> composed of <i>subject</i>,
-              <code>rdf:first</code>, and the result of using th
+            <li>Initialize <i>object</i> to the result of using the
               <a href="#object-to-rdf-conversion">Object to RDF Conversion algorithm</a>
               passing <i>item</i> to <i>list triples</i>.</li>
+            <li>Unless <i>object</i> is <a class="tref internalDFN" title="null" href="#dfn-null">null</a>, append a <a class="tref internalDFN" title="triple" href="http://www.w3.org/TR/rdf11-concepts/#dfn-rdf-triple">triple</a>
+              composed of <i>subject</i>, <code>rdf:first</code>, and <i>object</i>.</li>
             <li>Set <i>rest</i> as the next entry in <i>bnodes</i>, or if that
               does not exist, <code>rdf:nil</code>. Append a
               <a class="tref internalDFN" title="triple" href="http://www.w3.org/TR/rdf11-concepts/#dfn-rdf-triple">triple</a> composed of <i>subject</i>,
--- a/spec/CR/json-ld/20130822/diff-20130411.html	Tue Aug 20 22:52:51 2013 +0200
+++ b/spec/CR/json-ld/20130822/diff-20130411.html	Tue Aug 20 23:10:18 2013 +0200
@@ -17,7 +17,7 @@
  *****************************************************************/
 
 /* --- INLINES --- */
-em.rfc2119 { 
+em.rfc2119 {
     text-transform:     lowercase;
     font-variant:       small-caps;
     font-style:         normal;
@@ -126,7 +126,7 @@
     color: #b9ab2d;
 }
 div.example-title span {
-    text-transform: uppercase;   
+    text-transform: uppercase;
 }
 aside.example, div.example, div.illegal-example {
     padding: 0.5em;
@@ -141,7 +141,7 @@
     border-left-width: .5em;
     border-left-style: solid;
     border-color: #e0cb52;
-    background: #fcfaee;    
+    background: #fcfaee;
 }
 
 aside.example div.example {
@@ -400,7 +400,8 @@
 </span>
 </dd>
 </dl>
-<del class="diff-old">This
+<p>
+This
 document
 is
 also
@@ -409,11 +410,13 @@
 this
 non-normative
 format:
+<a rel="alternate" href="diff-20130411.html">
 diff
 to
 previous
 version
-</del>
+</a>
+</p>
 <p class="copyright">
 <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">
 Copyright
@@ -7360,7 +7363,102 @@
 </pre>
 </div>
 <p>
-<ins class="diff-chg">Setting
+<ins class="diff-new">Setting
+</ins><code><ins class="diff-new">
+@base
+</ins></code><ins class="diff-new">
+to
+</ins><a class="tref internalDFN" title="null" href="#dfn-null"><ins class="diff-new">
+null
+</ins></a><ins class="diff-new">
+will
+prevent
+</ins><a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri"><ins class="diff-new">
+relative
+IRIs
+</ins></a><ins class="diff-new">
+to
+be
+expanded
+to
+</ins><a class="tref internalDFN" title="absolute-iri" href="#dfn-absolute-iri"><ins class="diff-new">
+absolute
+IRIs
+</ins></a>.</p><div class="issue atrisk"><div class="issue-title" aria-level="3" role="heading" id="h_issue_1"><span><ins class="diff-new">
+Feature
+at
+Risk
+10
+</ins></span>:<ins class="diff-new">
+Support
+for
+@base:
+null
+</ins>
+</div>
+<div class="atrisk">
+<p class="atrisk-head">
+<ins class="diff-chg">Note:
+This
+feature
+is
+</ins><a href="http://www.w3.org/2005/10/Process-20051014/tr#cfi"><ins class="diff-chg">
+"at
+risk"
+</ins></a><ins class="diff-chg">
+and
+may
+be
+removed
+from
+this
+specification
+based
+on
+feedback.
+Please
+send
+feedback
+to
+</ins><a href="mailto:public-rdf-comments@w3.org"><ins class="diff-chg">
+public-rdf-comments@w3.org
+</ins></a>.<ins class="diff-chg">
+For
+the
+current
+status
+see
+</ins><a href="http://www.w3.org/2011/rdf-wg/wiki/JSON-LD_Features_at_Risk"><ins class="diff-chg">
+features
+"at
+risk"
+in
+JSON-LD
+1.0
+</ins></a></p><p><ins class="diff-chg">
+Unlike
+many
+other
+serialization
+formats,
+JSON-LD
+allows
+to
+specify
+that
+there
+is
+no
+base
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-chg">
+IRI
+</ins></abbr><ins class="diff-chg">
+from
+within
+the
+document
+(by
+setting
 </ins><code><ins class="diff-chg">
 @base
 </ins></code><ins class="diff-chg">
@@ -7368,20 +7466,90 @@
 </ins><a class="tref internalDFN" title="null" href="#dfn-null"><ins class="diff-chg">
 null
 </ins></a><ins class="diff-chg">
-will
-prevent
-</ins><a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri"><ins class="diff-chg">
-relative
-IRIs
+).
+The
+result
+is
+that
+the
+algorithm
+for
+establishing
+a
+base
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-chg">
+IRI
+</ins></abbr><ins class="diff-chg">
+as
+specified
+in
+</ins><a href="http://tools.ietf.org/html/rfc3986#section-5.1"><ins class="diff-chg">
+RFC3986
+section
+5.1
 </ins></a><ins class="diff-chg">
-to
-be
-expanded
-to
-</ins><a class="tref internalDFN" title="absolute-iri" href="#dfn-absolute-iri"><ins class="diff-chg">
-absolute
-IRIs
-</ins></a>.</p><p><ins class="diff-chg">
+is
+overridden
+so
+relative
+IRIs
+remain
+relative
+IRIs
+even
+in
+the
+case
+that
+an
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-chg">
+IRI
+</ins></abbr><ins class="diff-chg">
+would
+be
+available
+in
+one
+of
+the
+outer
+layers
+(e.g.,
+the
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-chg">
+IRI
+</ins></abbr><ins class="diff-chg">
+used
+to
+retrieve
+the
+document
+or
+an
+application
+supplied
+base
+</ins><abbr title="Internationalized Resource Identifier"><ins class="diff-chg">
+IRI
+</ins></abbr><ins class="diff-chg">
+).
+Based
+on
+implementer
+feedback,
+the
+Working
+Group
+may
+decide
+to
+remove
+this
+feature
+from
+JSON-LD
+1.0.
+</ins></p></div></div><p><ins class="diff-chg">
 Please
 note
 that
--- a/spec/CR/json-ld/20130822/index.html	Tue Aug 20 22:52:51 2013 +0200
+++ b/spec/CR/json-ld/20130822/index.html	Tue Aug 20 23:10:18 2013 +0200
@@ -17,7 +17,7 @@
  *****************************************************************/
 
 /* --- INLINES --- */
-em.rfc2119 { 
+em.rfc2119 {
     text-transform:     lowercase;
     font-variant:       small-caps;
     font-style:         normal;
@@ -126,7 +126,7 @@
     color: #b9ab2d;
 }
 div.example-title span {
-    text-transform: uppercase;   
+    text-transform: uppercase;
 }
 aside.example, div.example, div.illegal-example {
     padding: 0.5em;
@@ -141,7 +141,7 @@
     border-left-width: .5em;
     border-left-style: solid;
     border-color: #e0cb52;
-    background: #fcfaee;    
+    background: #fcfaee;
 }
 
 aside.example div.example {
@@ -210,8 +210,8 @@
       <dd><a class="u-url" href="http://www.w3.org/TR/2013/CR-json-ld-20130822/">http://www.w3.org/TR/2013/CR-json-ld-20130822/</a></dd>
       <dt>Latest published version:</dt>
       <dd><a href="http://www.w3.org/TR/json-ld/">http://www.w3.org/TR/json-ld/</a></dd>
-    
-    
+
+
       <dt>Latest editor's draft:</dt>
       <dd><a href="http://dvcs.w3.org/hg/json-ld/raw-file/default/spec/latest/json-ld/index.html">http://dvcs.w3.org/hg/json-ld/raw-file/default/spec/latest/json-ld/index.html</a></dd>
     
@@ -231,7 +231,7 @@
 <dd class="p-author h-card vcard" rel="bibo:editor" inlist=""><span typeof="foaf:Person"><a class="u-url url p-name fn" rel="foaf:homepage" property="foaf:name" content="Markus Lanthaler" href="http://www.markus-lanthaler.com/">Markus Lanthaler</a>, <a rel="foaf:workplaceHomepage" class="p-org org h-org h-card" href="http://www.tugraz.at/">Graz University of Technology</a></span>
 </dd>
 
-    
+
       <dt>Authors:</dt>
       <dd class="p-author h-card vcard" rel="dcterms:contributor"><span typeof="foaf:Person"><a class="u-url url p-name fn" rel="foaf:homepage" property="foaf:name" content="Manu Sporny" href="http://digitalbazaar.com/">Manu Sporny</a>, <a rel="foaf:workplaceHomepage" class="p-org org h-org h-card" href="http://digitalbazaar.com/">Digital Bazaar</a></span>
 </dd>
@@ -244,8 +244,8 @@
 <dd class="p-author h-card vcard" rel="dcterms:contributor"><span typeof="foaf:Person"><a class="u-url url p-name fn" rel="foaf:homepage" property="foaf:name" content="Niklas Lindström" href="http://neverspace.net/">Niklas Lindström</a></span>
 </dd>
 
-    
-    
+
+
   </dl>
   
   
@@ -270,8 +270,8 @@
         <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and
         <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply.
       </p>
-    
-  
+
+
   <hr>
 </div>
 <section id="abstract" class="introductory" property="dcterms:abstract" datatype="" typeof="bibo:Chapter" resource="#abstract" rel="bibo:chapter"><h2 aria-level="1" role="heading" id="h2_abstract">Abstract</h2>
@@ -284,16 +284,16 @@
     programming environments, to build interoperable Web services, and to
     store Linked Data in JSON-based storage engines.</p>
 </section><section id="sotd" class="introductory" typeof="bibo:Chapter" resource="#sotd" rel="bibo:chapter"><h2 aria-level="1" role="heading" id="h2_sotd">Status of This Document</h2>
-  
-    
-      
+
+
+
         <p>
           <em>This section describes the status of this document at the time of its publication. Other
           documents may supersede this document. A list of current <abbr title="World Wide Web Consortium">W3C</abbr> publications and the latest revision
           of this technical report can be found in the <a href="http://www.w3.org/TR/"><abbr title="World Wide Web Consortium">W3C</abbr> technical reports
           index</a> at http://www.w3.org/TR/.</em>
         </p>
-        
+
   <p>This document has been under development for over 30 months in the
     JSON for Linking Data Community Group. The document has been
     transferred to the RDF Working Group for review, improvement, and publication.
@@ -360,11 +360,11 @@
   </ul>
 
   <p>
-    Before this specification may exit the Candidate Recommendation phase, 
-    at least two independent implementations must pass each test, 
-    although no single implementation must pass every test. The 
-    working group will decide when 
-    the test suite is of sufficient quality to test interoperability and 
+    Before this specification may exit the Candidate Recommendation phase,
+    at least two independent implementations must pass each test,
+    although no single implementation must pass every test. The
+    working group will decide when
+    the test suite is of sufficient quality to test interoperability and
     will produce an implementation report hosted together with the test suite.
   </p>
 
@@ -396,32 +396,32 @@
             This is a draft document and may be updated, replaced or obsoleted by other documents at 
             any time. It is inappropriate to cite this document as other than work in progress.
           </p>
-        
-        
+
+
         <p>
-          
-            This document was produced by a group operating under the 
-             
+
+            This document was produced by a group operating under the
+
                 <a id="sotd_patent" about="" rel="w3p:patentRules" href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 February 2004 <abbr title="World Wide Web Consortium">W3C</abbr> Patent Policy</a>.
-            
-          
-          
-          
-            
-              <abbr title="World Wide Web Consortium">W3C</abbr> maintains a <a href="http://www.w3.org/2004/01/pp-impl/46168/status" rel="disclosure">public list of any patent disclosures</a> 
-            
-            made in connection with the deliverables of the group; that page also includes instructions for 
+
+
+
+
+
+              <abbr title="World Wide Web Consortium">W3C</abbr> maintains a <a href="http://www.w3.org/2004/01/pp-impl/46168/status" rel="disclosure">public list of any patent disclosures</a>
+
+            made in connection with the deliverables of the group; that page also includes instructions for
             disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains
             <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential Claim(s)</a> must disclose the
             information in accordance with <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section
             6 of the <abbr title="World Wide Web Consortium">W3C</abbr> Patent Policy</a>.
-          
-          
+
+
         </p>
-        
-      
-    
-  
+
+
+
+
 </section><section id="toc"><h2 class="introductory" aria-level="1" role="heading" id="h2_toc">Table of Contents</h2><ul class="toc" role="directory" id="respecContents"><li class="tocline"><a href="#introduction" class="tocxref"><span class="secno">1. </span>Introduction</a><ul class="toc"><li class="tocline"><a href="#how-to-read-this-document" class="tocxref"><span class="secno">1.1 </span>How to Read this Document</a></li></ul></li><li class="tocline"><a href="#design-goals-and-rationale" class="tocxref"><span class="secno">2. </span>Design Goals and Rationale</a></li><li class="tocline"><a href="#terminology" class="tocxref"><span class="secno">3. </span>Terminology</a><ul class="toc"><li class="tocline"><a href="#general-terminology" class="tocxref"><span class="secno">3.1 </span>General Terminology</a></li><li class="tocline"><a href="#data-model-overview" class="tocxref"><span class="secno">3.2 </span>Data Model Overview</a></li><li class="tocline"><a href="#syntax-tokens-and-keywords" class="tocxref"><span class="secno">3.3 </span>Syntax Tokens and Keywords</a></li></ul></li><li class="tocline"><a href="#conformance" class="tocxref"><span class="secno">4. </span>Conformance</a></li><li class="tocline"><a href="#basic-concepts" class="tocxref"><span class="secno">5. </span>Basic Concepts</a><ul class="toc"><li class="tocline"><a href="#the-context" class="tocxref"><span class="secno">5.1 </span>The Context</a></li><li class="tocline"><a href="#iris" class="tocxref"><span class="secno">5.2 </span>IRIs</a></li><li class="tocline"><a href="#node-identifiers" class="tocxref"><span class="secno">5.3 </span>Node Identifiers</a></li><li class="tocline"><a href="#specifying-the-type" class="tocxref"><span class="secno">5.4 </span>Specifying the Type</a></li></ul></li><li class="tocline"><a href="#advanced-concepts" class="tocxref"><span class="secno">6. </span>Advanced Concepts</a><ul class="toc"><li class="tocline"><a href="#base-iri" class="tocxref"><span class="secno">6.1 </span>Base <abbr title="Internationalized Resource Identifier">IRI</abbr></a></li><li class="tocline"><a href="#default-vocabulary" class="tocxref"><span class="secno">6.2 </span>Default Vocabulary</a></li><li class="tocline"><a href="#compact-iris" class="tocxref"><span class="secno">6.3 </span>Compact IRIs</a></li><li class="tocline"><a href="#typed-values" class="tocxref"><span class="secno">6.4 </span>Typed Values</a></li><li class="tocline"><a href="#type-coercion" class="tocxref"><span class="secno">6.5 </span>Type Coercion</a></li><li class="tocline"><a href="#embedding" class="tocxref"><span class="secno">6.6 </span>Embedding</a></li><li class="tocline"><a href="#advanced-context-usage" class="tocxref"><span class="secno">6.7 </span>Advanced Context Usage</a></li><li class="tocline"><a href="#interpreting-json-as-json-ld" class="tocxref"><span class="secno">6.8 </span>Interpreting JSON as JSON-LD</a></li><li class="tocline"><a href="#string-internationalization" class="tocxref"><span class="secno">6.9 </span>String Internationalization</a></li><li class="tocline"><a href="#iri-expansion-within-a-context" class="tocxref"><span class="secno">6.10 </span><abbr title="Internationalized Resource Identifier">IRI</abbr> Expansion within a Context</a></li><li class="tocline"><a href="#sets-and-lists" class="tocxref"><span class="secno">6.11 </span>Sets and Lists</a></li><li class="tocline"><a href="#reverse-properties" class="tocxref"><span class="secno">6.12 </span>Reverse Properties</a></li><li class="tocline"><a href="#named-graphs" class="tocxref"><span class="secno">6.13 </span>Named Graphs</a></li><li class="tocline"><a href="#identifying-blank-nodes" class="tocxref"><span class="secno">6.14 </span>Identifying Blank Nodes</a></li><li class="tocline"><a href="#aliasing-keywords" class="tocxref"><span class="secno">6.15 </span>Aliasing Keywords</a></li><li class="tocline"><a href="#data-indexing" class="tocxref"><span class="secno">6.16 </span>Data Indexing</a></li><li class="tocline"><a href="#expanded-document-form" class="tocxref"><span class="secno">6.17 </span>Expanded Document Form</a></li><li class="tocline"><a href="#compacted-document-form" class="tocxref"><span class="secno">6.18 </span>Compacted Document Form</a></li><li class="tocline"><a href="#flattened-document-form" class="tocxref"><span class="secno">6.19 </span>Flattened Document Form</a></li><li class="tocline"><a href="#embedding-json-ld-in-html-documents" class="tocxref"><span class="secno">6.20 </span>Embedding JSON-LD in HTML Documents</a></li></ul></li><li class="tocline"><a href="#data-model" class="tocxref"><span class="secno">7. </span>Data Model</a></li><li class="tocline"><a href="#json-ld-grammar" class="tocxref"><span class="secno">8. </span>JSON-LD Grammar</a><ul class="toc"><li class="tocline"><a href="#terms" class="tocxref"><span class="secno">8.1 </span>Terms</a></li><li class="tocline"><a href="#node-objects" class="tocxref"><span class="secno">8.2 </span>Node Objects</a></li><li class="tocline"><a href="#value-objects" class="tocxref"><span class="secno">8.3 </span>Value Objects</a></li><li class="tocline"><a href="#lists-and-sets" class="tocxref"><span class="secno">8.4 </span>Lists and Sets</a></li><li class="tocline"><a href="#language-maps" class="tocxref"><span class="secno">8.5 </span>Language Maps</a></li><li class="tocline"><a href="#index-maps" class="tocxref"><span class="secno">8.6 </span>Index Maps</a></li><li class="tocline"><a href="#context-definitions" class="tocxref"><span class="secno">8.7 </span>Context Definitions</a></li></ul></li><li class="tocline"><a href="#relationship-to-rdf" class="tocxref"><span class="secno">9. </span>Relationship to RDF</a><ul class="toc"><li class="tocline"><a href="#serializing-deserializing-rdf" class="tocxref"><span class="secno">9.1 </span>Serializing/Deserializing RDF</a></li></ul></li><li class="tocline"><a href="#relationship-to-other-linked-data-formats" class="tocxref"><span class="secno">A. </span>Relationship to Other Linked Data Formats</a><ul class="toc"><li class="tocline"><a href="#turtle" class="tocxref"><span class="secno">A.1 </span>Turtle</a></li><li class="tocline"><a href="#rdfa" class="tocxref"><span class="secno">A.2 </span>RDFa</a></li><li class="tocline"><a href="#microformats" class="tocxref"><span class="secno">A.3 </span>Microformats</a></li><li class="tocline"><a href="#microdata" class="tocxref"><span class="secno">A.4 </span>Microdata</a></li></ul></li><li class="tocline"><a href="#iana-considerations" class="tocxref"><span class="secno">B. </span>IANA Considerations</a></li><li class="tocline"><a href="#acknowledgements" class="tocxref"><span class="secno">C. </span>Acknowledgements</a></li><li class="tocline"><a href="#references" class="tocxref"><span class="secno">D. </span>References</a><ul class="toc"><li class="tocline"><a href="#normative-references" class="tocxref"><span class="secno">D.1 </span>Normative references</a></li><li class="tocline"><a href="#informative-references" class="tocxref"><span class="secno">D.2 </span>Informative references</a></li></ul></li></ul></section>
 
 
@@ -837,7 +837,7 @@
 }</pre></div>
 
     <p>The referenced context not only specifies how the terms map to
-      <a class="tref internalDFN" title="iri" href="#dfn-iri">IRIs</a> in the Schema.org vocabulary but also 
+      <a class="tref internalDFN" title="iri" href="#dfn-iri">IRIs</a> in the Schema.org vocabulary but also
       specifies that string values associated with
       the <code>homepage</code> and <code>image</code> property
       can be interpreted as an <a class="tref internalDFN" title="iri" href="#dfn-iri"><abbr title="Internationalized Resource Identifier">IRI</abbr></a> (<code>"@type": "@id"</code>,
@@ -1118,7 +1118,25 @@
     <a class="tref internalDFN" title="relative-iri" href="#dfn-relative-iri">relative IRIs</a> to be expanded to
     <a class="tref internalDFN" title="absolute-iri" href="#dfn-absolute-iri">absolute IRIs</a>.</p>
 
-  <p>Please note that the <code>@base</code> will be ignored if used in external contexts.</p>
+  <div class="issue atrisk"><div class="issue-title" aria-level="3" role="heading" id="h_issue_1"><span>Feature at Risk 10</span>: Support for @base: null </div><div class="atrisk">
+    <p class="atrisk-head">Note: This feature is
+      <a href="http://www.w3.org/2005/10/Process-20051014/tr#cfi">"at risk"</a> and may
+      be removed from this specification based on feedback. Please send feedback to
+      <a href="mailto:public-rdf-comments@w3.org">public-rdf-comments@w3.org</a>.
+      For the current status see
+      <a href="http://www.w3.org/2011/rdf-wg/wiki/JSON-LD_Features_at_Risk">features "at risk" in JSON-LD 1.0</a></p>
+   <p>Unlike many other serialization formats, JSON-LD allows to specify that
+    there is no base <abbr title="Internationalized Resource Identifier">IRI</abbr> from within the document (by setting <code>@base</code> to
+    <a class="tref internalDFN" title="null" href="#dfn-null">null</a>). The result is that the algorithm for establishing a base <abbr title="Internationalized Resource Identifier">IRI</abbr>
+    as specified in <a href="http://tools.ietf.org/html/rfc3986#section-5.1">RFC3986 section 5.1</a>
+    is overridden so relative IRIs remain relative IRIs even in the case that an <abbr title="Internationalized Resource Identifier">IRI</abbr>
+    would be available in one of the outer layers (e.g., the <abbr title="Internationalized Resource Identifier">IRI</abbr> used to retrieve
+    the document or an application supplied base <abbr title="Internationalized Resource Identifier">IRI</abbr>). Based on implementer feedback,
+    the Working Group may decide to remove this feature from JSON-LD 1.0.</p>
+  </div></div>
+
+  <p>Please note that the <code>@base</code> will be ignored if used in
+    external contexts.</p>
 </section>
 
 <section class="informative" id="default-vocabulary">