- From: Ian Hickson via cvs-syncmail <cvsmail@w3.org>
- Date: Tue, 14 Jul 2009 05:00:12 +0000
- To: public-html-commits@w3.org
Update of /sources/public/html5/spec In directory hutz:/tmp/cvs-serv18845 Modified Files: Overview.html Log Message: Introduce more magic for document.all. (whatwg r3403) Index: Overview.html =================================================================== RCS file: /sources/public/html5/spec/Overview.html,v retrieving revision 1.2532 retrieving revision 1.2533 diff -u -d -r1.2532 -r1.2533 --- Overview.html 14 Jul 2009 03:17:27 -0000 1.2532 +++ Overview.html 14 Jul 2009 05:00:08 -0000 1.2533 @@ -65032,15 +65032,31 @@ attribute must return an <code><a href="#htmlcollection-0">HTMLCollection</a></code> rooted at the <code>Document</code> node, whose filter matches all elements.</p> - <p>The user agent must act as if the ToBoolean() operator in - JavaScript converted the object returned for <code title="dom-document-all"><a href="#dom-document-all">all</a></code> to the false value.</p> + <p>The object returned for <code title="dom-document-all"><a href="#dom-document-all">all</a></code> + has several unusual behaviors:</p> - <p class="note">This is a <a href="#willful-violation">willful violation</a> of the - JavaScript specification current at the time of writing (ECMAScript - edition 3). The JavaScript specification requires that the - ToBoolean() operator convert all objects to the true value. This - violation is motivated by a desire for compatibility with legacy - content. <a href="#references">[ECMA262]</a></p> + <ul><li><p>The user agent must act as if the ToBoolean() operator in + JavaScript converts the object returned for <code title="dom-document-all"><a href="#dom-document-all">all</a></code> to the false value.</li> + + <li><p>The user agent must act as if, for the purposes of the <code title="">==</code> and <code title="">!=</code> operators in + JavaScript, the object returned for <code title="dom-document-all"><a href="#dom-document-all">all</a></code> is equal to the <code title="">undefined</code> value.</li> + + <li><p>The user agent must act such that the <code title="">typeof</code> operator in JavaScript returns the string + <code title="">undefined</code> when applied to the object returned + for <code title="dom-document-all"><a href="#dom-document-all">all</a></code>.</li> + + </ul><p class="note">These requirements are a <a href="#willful-violation">willful + violation</a> of the JavaScript specification current at the time + of writing (ECMAScript edition 3). The JavaScript specification + requires that the ToBoolean() operator convert all objects to the + true value, and does not have provisions for objects acting as if + they were <code title="">undefined</code> for the purposes of + certain operators. This violation is motivated by a desire for + compatibility with two classes of legacy content: one that uses the + presence of <code title="dom-document-all"><a href="#dom-document-all">document.all</a></code> as a + way to detect legacy user agents, and one that only supports those + legacy user agents and uses the <code title="dom-document-all"><a href="#dom-document-all">document.all</a></code> object without testing + for its presence first. <a href="#references">[ECMA262]</a></p> </div><h2 id="no"><span class="secno">13 </span>Things that you can't do with this specification because they are better handled using other technologies that are further
Received on Tuesday, 14 July 2009 05:00:22 UTC