Update language around version similar to recent changes in N-Triples.

spec/index.html

@@ -229,10 +229,14 @@ <h2>Turtle Language</h2>
 
   <section id="simple-triples">
     <h3>Simple Triples</h3>
-    <p>The simplest triple statement is a sequence of (subject, predicate, object) terms,
-      separated by white space
-      (<a href="#cp-space"><code title="space">spaces</code></a>, and/or <a href="#cp-tab"><code title="horizontal tab">tabs</code></a>)
-      and terminated by <a href="#cp-full-stop"><code title="full stop">.</code></a> after the object.</p>
+    <p>The simplest triple statement is a sequence of
+      (<a data-cite="RDF12-CONCEPTS#dfn-subject">subject</a>,
+      <a data-cite="RDF12-CONCEPTS#dfn-predicate">predicate</a>,
+      <a data-cite="RDF12-CONCEPTS#dfn-object">object</a>) terms,
+      forming an <a data-cite="RDF12-CONCEPTS#dfn-rdf-triple">RDF triple</a>
+      and terminated by <a href="#cp-full-stop"><code title="full stop">.</code></a>.
+      White space (<a href="#cp-space"><code title="space">spaces</code></a>, and/or <a href="#cp-tab"><code title="horizontal tab">tabs</code></a>) may surround terms,
+      except where significant as noted in the <a href="#sec-grammar-grammar">grammar</a>.</p>
     <pre id="ex-simple-triple"
          class="example turtle" data-transform="updateExample"
          title="Simple Triple">
@@ -1916,8 +1920,10 @@ <h3>Parser State</h3>
         The RDF version used for parsing the document into <a data-cite="RDF12-CONCEPTS#dfn-rdf-triple">Triples</a>.
         If specified as part of a <a href="#sec-mediaReg">Media Type</a>, the default value for |curVersion| is taken from the `version` parameter.
         Acceptable values for `version` are defined in <a data-cite="RDF12-CONCEPTS#defined-version-labels">2.1 Version Lables</a> in [[RDF12-CONCEPTS]].
-        Parser behavior for version values is undefined and MAY be used
-        to signal errors or warnings.
+        The version announcement is only a hint;
+        this specification does not mandate any parser behavior based on |curVersion|,
+        but a parser MAY signal an error or a warning
+        when it encounters a feature that does not match the value of |curVersion|.
       </li>
     </ul>
 
@@ -2360,7 +2366,9 @@ <h2>Internet Media Type, File Extension and Macintosh File Type</h2>
     <dd>None</dd>
     <dt>Optional parameters:</dt>
     <dd><code>charset</code> — this parameter is required when transferring non-ASCII data. If present, the value of <code>charset</code> is always <code>UTF-8</code>.</dd>
-    <dd><code>version</code> — this parameter is required when using RDF 1.2-specific features. If present, the value of <code>version</code> is always <code>"1.2"</code>.</dd>
+    <dd><code>version</code> — this parameter is optional but SHOULD be present when using RDF 1.2-specific features.
+      If present, acceptable values of <code>version</code> are
+      defined in <a data-cite="RDF12-CONCEPTS#defined-version-labels">2.1 Version Lables</a> in [[RDF12-CONCEPTS]].</dd>
 
     <dt>Encoding considerations:</dt>
     <dd>The syntax of Turtle is expressed over code points in Unicode [[!UNICODE]]. The encoding is always UTF-8 [[!UTF-8]].</dd>