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wakaba |
1.1 |
<!DOCTYPE html><html id="error-description" lang="en" xmlns:d="http://suika.fam.cx/~wakaba/archive/2007/wdcc-desc/" xmlns="http://www.w3.org/1999/xhtml"> |
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<head> |
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<title xml:lang="en">Description of Errors — |
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Web Document Conformance Checker (BETA)</title> |
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<link href="cc-style" rel="stylesheet"> |
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<link href="#license" rel="license"> |
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</head> |
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<body> |
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<h1>Description of Errors</h1> |
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wakaba |
1.2 |
<section id="html5-tokenize-error"> |
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<h2>HTML5 Parse Errors in Tokenization Stage</h2> |
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wakaba |
1.1 |
|
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wakaba |
1.3 |
<div class="section parse-error" id="after-html"><h3>Tag <code><<var>$0</var>></code> |
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is not allowed after the end tag <code></html></code>.</h3> |
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<p>The start or end tag of an element appears after the |
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<code>html</code> element has been closed. The document is |
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non-conforming.</p> |
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<p>Any content of the document other than comments |
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must be put into the <code>html</code> element.</p> |
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</div> |
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<div class="section tokenize-error" id="bare-ero"><h3>The <code>&</code> character must |
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introduce a reference.</h3> |
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<p>An <code>&</code> (<code>U+0026</code> |
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<code class="charname">AMPERSAND</code>) character which |
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is not part of any reference appears in the input stream. |
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The document is non-conforming.</p> |
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<p>The <code>&</code> character must |
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be the first character of a reference: |
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<dl> |
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<dt>Named entity reference</dt> |
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<dd><pre class="html example"> |
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<code>&<var>entity-name</var>;</code></pre> |
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where <var>entity-name</var> is the name of the |
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character entity to be referenced.</dd> |
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<dt>Numeric character reference</dt> |
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<dd><pre class="html example"> |
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<code>&#<var>d</var>;</code></pre> |
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where <var>d</var> is the decimal representation of |
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the code position of the character to be referenced.</dd> |
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<dt>Hexadecimal character reference</dt> |
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<dd><pre class="html example"> |
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<code>&#x<var>h</var>;</code></pre> |
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where <var>h</var> is the hexadecimal representation |
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of the code position of the character to be referenced.</dd> |
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</dl> |
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</p> |
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<p>To represent <code>&</code> as a data character, use |
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named entity reference: |
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<pre class="html example"> |
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<code>&amp;</code></pre> |
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</p> |
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</div> |
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wakaba |
1.4 |
<div class="section tokenize-error" id="bare-stago"><h3>A <code><</code> character is not followed |
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by tag name or by a <code>!</code> character.</h3> |
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<p>A <code><</code> (<code>U+003C</code> <code class="charname">LESS-THAN |
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SIGN</code>) character which is not part of any markup appears |
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in the input stream.</p> |
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<p>The <code><</code> character as a data character must |
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be escaped as: |
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<pre class="html example"> |
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<code><lt;</code></pre> |
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</p> |
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</div> |
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wakaba |
1.3 |
<div class="section tokenize-error" id="bare-nero"><h3>The decimal representation of the code position |
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of a character must be specified after <code>&#</code>.</h3> |
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<p>An <code>&</code> (<code>U+0026</code> |
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<code class="charname">AMPERSAND</code>) character immediately |
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followed by a <code>#</code> (<code>U+0023</code> |
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<code>NUMBER SIGN</code>) character which |
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is not part of any reference appears in the input stream. |
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The document is non-conforming.</p> |
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<p>The string <code>&#</code> must be the first two characters |
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<code>NUMBER SIGN</code>) character must be the first two characters |
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of a reference: |
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<dl> |
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<dt>Numeric character reference</dt> |
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<dd><pre class="html example"> |
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<code>&#<var>d</var>;</code></pre> |
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where <var>d</var> is the decimal representation of |
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the code point of the character to be referenced.</dd> |
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<dt>Hexadecimal character reference</dt> |
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<dd><pre class="html example"> |
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<code>&#x<var>h</var>;</code></pre> |
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where <var>h</var> is the hexadecimal representation |
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of the code point of the character to be referenced.</dd> |
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</dl> |
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</p> |
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<p>To represent <code>&#</code> as data characters, use |
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named entity reference: |
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<pre class="html example"> |
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<code>&amp;#</code></pre> |
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</p> |
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</div> |
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<div class="section tokenize-error" id="bare-hcro"><h3>The hexadecimal representation of the code position |
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of a character must be specified after <code>&#x</code>.</h3> |
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<p>The string <code>&#x</code> or <code>&#X</code> which |
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is not part of any reference appears in the input stream. |
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The document is non-conforming.</p> |
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<p>The string <code>&#x</code> or <code>&#X</code> must |
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be the first three characters of a hexadecimal reference: |
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<pre class="html example"> |
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<code>&#x<var>h</var>;</code></pre> |
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where <var>h</var> is the hexadecimal representation |
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of the code point of the character to be referenced.</p> |
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<p>To represent <code>&#x</code> as data characters, use |
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named entity reference: |
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<pre class="html example"> |
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<code>&amp;#x</code></pre> |
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</p> |
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</div> |
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wakaba |
1.4 |
<div class="section tokenize-error" id="dash-in-comment"><h3>There is a <code>--</code> sequence |
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in a comment.</h3> |
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<p>There is a <code>-</code> (<code>U+002D</code> |
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<code class="charname">HYPHEN-MINUS</code>) character |
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at the end of the comment or a <code>--</code> sequence |
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in the comment. The document is non-conforming.</p> |
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<p>Comments cannot contain a string <code>--</code>, as in XML. |
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Unlike SGML, there cannot be more than one comments |
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(where <i>comment</i> is an SGML term) in the comment |
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declaration.</p> |
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</div> |
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wakaba |
1.1 |
<div class="section tokenize-error" id="duplicate-attribute"><h3>There are two attributes with same name.</h3> |
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wakaba |
1.3 |
<p>There are more than one attributes with the same |
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name in a tag. The document is non-conforming.</p> |
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wakaba |
1.1 |
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<p>The <code>motion</code> attribute is not part of the HTML standard. |
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Use <code>img</code> element with animation GIF instead.</p> |
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</div> |
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<div class="section tokenize-error" id="nestc"><h3>Void element syntax (<code>/></code>) cannot be |
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used for this element.</h3> |
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wakaba |
1.3 |
<p>Void element syntax (<code>/></code>) must not be used |
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for the element. The document is non-conforming.</p> |
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<p>The void element syntax can only be |
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wakaba |
1.1 |
used for <code>base</code>, <code>link</code>, <code>meta</code>, |
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<code>hr</code>, <code>br</code>, <code>img</code>, |
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<code>embed</code>, <code>param</code>, <code>area</code>, |
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wakaba |
1.3 |
<code>col</code>, and <code>input</code> elements.</p> |
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wakaba |
1.1 |
|
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wakaba |
1.3 |
<p>Note that, unlike in XML, the void element syntax has |
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wakaba |
1.1 |
no effect in HTML.</p> |
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</div> |
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wakaba |
1.5 |
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<div class="section tokenize-error" id="pio"><h3>Processing instruction |
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(<code><?<var>...</var>?></code>) cannot be used.</h3> |
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<p>Processing instructions (<code><?<var>...</var>?></code>), |
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including XML declaration (<code><?xml <var>...</var>?></code>) |
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and XML style sheet <abbr title="processing instruction">PI</abbr> |
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(<code><xml-stylesheet <var>...</var>?></code>), are not allowed |
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in the HTML syntax. The document is non-conforming.</p> |
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<p>If it is necessary to embed a processing instruction |
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in the HTML document, you must use the XML syntax instead.</p> |
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<p>In the HTML syntax, XML declaration is not necessary.</p> |
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<p>Instead of XML style sheet, |
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<abbr title="processing instruction">PI</abbr>s, you must |
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use the HTML <code>link</code> element whose <code>rel</code> |
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attribute is set to <code>stylesheet</code> (or <code>alternate |
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stylesheet</code> for an aleternate style sheet).</p> |
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<p>Web browsers will parse processing instructions as bogus |
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comments. Some legacy Web browsers, such as IE:mac and |
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some mobile browsers, will display processing instructions |
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as string.</p> |
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</div> |
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wakaba |
1.1 |
</section> |
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wakaba |
1.2 |
<section id="html5-parse-errors"> |
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<h2>HTML5 Parse Errors in Tree Construction Stage</h2> |
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<div class="section parse-error" id="after-head"><h3>The <code><var>$0</var></code> element cannot be |
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inserted between <code>head</code> and <code>body</code> elements.</h3> |
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wakaba |
1.3 |
<p>A start tag appears after the <code>head</code> element is closed |
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wakaba |
1.2 |
but before the <code>body</code> element is opened. |
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The document is non-conforming.</p> |
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</div> |
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wakaba |
1.4 |
<div class="section parse-error" id="DOCTYPE-in-the-middle"><h3>A <code>DOCTYPE</code> appears after any |
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element or data character has been seen.</h3> |
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<p>A <code>DOCTYPE</code> appears after any element or data character |
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has been seen. The document is non-conforming.</p> |
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<p>The <code>DOCTYPE</code> must be placed before any |
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tag, reference, or data character. Only white space characters |
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and comments can be inserted before the <code>DOCTYPE</code>.</p> |
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</div> |
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wakaba |
1.5 |
<div class="section parse-error" id="in-a:a"><h3>Anchor cannot be nested.</h3> |
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<p>HTML <code>a</code> elements cannot be nested. |
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The document is non-conforming.</p> |
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<p>In the HTML syntax, a start tag of the <code>a</code> |
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implies the end tag of any opening <code>a</code> element.</p> |
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</div> |
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wakaba |
1.4 |
<div class="section parse-error" id="in-body"><h3>Tag <code><<var>$0</var>></code> |
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is not allowed in <code>body</code>.</h3> |
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<p>The start or end tag of an element, which |
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cannot be a descendant of <code>body</code> element, appears |
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in the input stream while the <code>body</code> element has been opened. |
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The document is non-conforming.</p> |
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</div> |
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wakaba |
1.3 |
<div class="section parse-error" id="in-table"><h3>Tag <code><<var>$0</var>></code> |
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is not allowed in <code>table</code>.</h3> |
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wakaba |
1.4 |
<p>The start or end tag of an element, which |
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cannot be a child of <code>table</code> element, appears |
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in the input stream while the <code>table</code> element has been opened |
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but no other element has been opened. The document is non-conforming.</p> |
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wakaba |
1.3 |
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<p>In <code>table</code>, only table related elements |
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are allowed; any other element must be contained in |
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<code>td</code> or <code>th</code> element to form |
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a part of the table, or <code>caption</code> element to create |
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a table caption.</p> |
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</div> |
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<div class="section parse-error" id="in-table:#character"><h3>Data character is not allowed in |
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<code>table</code>.</h3> |
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<p>A data character appears in <code>table</code>. The document |
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is non-conforming.</p> |
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<p>In <code>table</code>, only table related elements |
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are allowed; any other element and data character must be contained in |
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<code>td</code> or <code>th</code> element to form |
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a part of the table, or <code>caption</code> element to create |
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a table caption.</p> |
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</div> |
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<div class="section parse-error" id="missing-start-tag:tr"><h3>Start tag of <code>tr</code> |
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element is missing.</h3> |
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<p>Start tag of a <code>tr</code> element, which is <em>not</em> |
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optional, is missing. The document is non-conforming.</p> |
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<p>In a table section, a <code><tr></code> start tag |
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must occur before any <code><td></code> or |
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<code><th></code> start tag. Though the HTML5 parser |
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implies the <code><tr></code> start tag before |
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these start tags, it must be explicitly specified.</p> |
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</div> |
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wakaba |
1.2 |
<div class="section parse-error" id="no-DOCTYPE"><h3>This document does not start with the |
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wakaba |
1.3 |
<code>DOCTYPE</code>.</h3> |
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<p>The document does not start with a <code>DOCTYPE</code>. |
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The document is non-conforming.</p> |
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<p>An HTML document must start by a <code>DOCTYPE</code>: |
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<pre class="html example"> |
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<code><!DOCTYPE HTML></code></pre> |
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</p> |
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<p>Only white space characters and comments are allowed |
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before the <code>DOCTYPE</code>.</p> |
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</div> |
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wakaba |
1.2 |
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<div class="section parse-error" id="not-closed"><h3>Element <code><var>$0</var></code> is not |
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wakaba |
1.3 |
closed.</h3> |
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<p>End tag of an element is not found before, for example, |
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an end tag of another element appears or |
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the end of the document. The document is non-conforming.</p> |
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</div> |
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wakaba |
1.2 |
|
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<div class="section parse-error" id="not-HTML5"><h3>This document is written in an old version of |
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wakaba |
1.3 |
HTML.</h3> |
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<p>The document contains a <code>DOCTYPE</code> declaration |
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that is different from HTML5 <code>DOCTYPE</code> (i.e. <code><!DOCTYPE |
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HTML></code>). The document is non-conforming.</p> |
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<p>The document might or might not be conformant to |
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some version of HTML. However, conformance to any HTML |
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specification other than HTML5 provides for no practical |
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convenience, since Web borwsers will parse any |
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HTML document (roughly) as defined in HTML5.</p> |
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</div> |
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wakaba |
1.2 |
|
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<div class="section parse-error" id="unmatched-end-tag"><h3>Element <code><var>$0</var></code> is not |
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wakaba |
1.4 |
opened.</h3> |
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<p>An end tag appears though no element with the same name |
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has been opened. The document is non-conforming.</p> |
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<p>For any end tag in HTML document, there must be a |
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corresponding start tag.</p> |
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</div> |
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wakaba |
1.2 |
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</section> |
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wakaba |
1.1 |
<section id="element-content-model-errors"> |
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<h2>Element Content Model Errors</h2> |
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<div class="section content-model-error" id="character-not-allowed"><h3>Data character is not allowed in this |
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context.</h3> |
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wakaba |
1.3 |
<p>A data character appears where it is not allowed in this |
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wakaba |
1.1 |
context. The document is non-conforming.</p> |
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<p>Possible causes: |
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<dl> |
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<dt>If the erred element is an inline-level element (such |
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as <code>a</code> or <code>span</code>)</dt> |
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<dd><p>A data character cannot be a child |
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of certain sectioning elements such as <code>body</code>, |
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<code>section</code>, and <code>blockquote</code>.</p> |
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<p>Any inline-level content must be put |
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in e.g. paragraph element such as <code>p</code>.</p></dd> |
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<dt>If the erred element is a block-level element (such as |
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|
|
<code>div</code> or <code>h<var>n</var></code>)</dt> |
328 |
|
|
<dd><p>Though some elements such as <code>div</code>, |
329 |
|
|
<code>li</code>, and <code>td</code> allow |
330 |
|
|
<em>either one</em> of block-level or inline-level content |
331 |
|
|
is allowed. If there is a block-level content, |
332 |
|
|
any inline-level content must be put |
333 |
|
|
in e.g. paragraph element such as <code>p</code>.</p></dd> |
334 |
|
|
</dl> |
335 |
|
|
</p> |
336 |
|
|
</div> |
337 |
|
|
|
338 |
|
|
<div class="section content-model-error" id="child-element-missing"><h3>There must be a <code><var>$0</var></code> |
339 |
|
|
element as a child of this element.</h3> |
340 |
|
|
<p>The content model of the element is so defined that it |
341 |
|
|
must contain a <code><var>$0</var></code> child element. |
342 |
wakaba |
1.3 |
The document is non-conforming.</p> |
343 |
wakaba |
1.1 |
|
344 |
|
|
<p>For example: |
345 |
|
|
<ul> |
346 |
|
|
<li>The <code>head</code> element must contain exactly one |
347 |
|
|
<code>title</code> child element.</li> |
348 |
|
|
<li><a href="#child-element-missing:td%7Cth">The <code>tr</code> |
349 |
|
|
element must contain one or more <code>td</code> or <code>th</code> |
350 |
|
|
child element.</a></li> |
351 |
|
|
</ul> |
352 |
|
|
</p> |
353 |
|
|
</div> |
354 |
|
|
|
355 |
|
|
<div class="section content-model-error" id="child-element-missing:td|th"><h3>There must be a <code>td</code> |
356 |
|
|
or <code>th</code> element as a child of this element.</h3> |
357 |
|
|
<p>The <code>tr</code> element must contain at least one |
358 |
wakaba |
1.3 |
<code>td</code> or <code>th</code> child element. The document |
359 |
|
|
is non-conforming.</p> |
360 |
wakaba |
1.1 |
</div> |
361 |
|
|
|
362 |
|
|
<div class="section content-model-error" id="element-not-allowed"><h3>This element is not allowed in this |
363 |
|
|
context.</h3> |
364 |
wakaba |
1.3 |
<p>An element appears where it is not allowed. The document |
365 |
wakaba |
1.1 |
is non-conforming.</p> |
366 |
|
|
|
367 |
wakaba |
1.3 |
<p><strong>Note</strong>: The conformance checker does |
368 |
|
|
<em>not</em> support form elements yet.</p> |
369 |
|
|
|
370 |
wakaba |
1.1 |
<p>Possible causes: |
371 |
|
|
<dl> |
372 |
|
|
<dt>If the erred element is an inline-level element (such |
373 |
|
|
as <code>a</code> or <code>span</code>)</dt> |
374 |
|
|
<dd><p>An inline-level element cannot be a child |
375 |
|
|
of certain sectioning elements such as <code>body</code>, |
376 |
|
|
<code>section</code>, and <code>blockquote</code>.</p> |
377 |
|
|
|
378 |
|
|
<p>Any inline-level content must be put |
379 |
|
|
in e.g. paragraph element such as <code>p</code>.</p></dd> |
380 |
|
|
<dt>If the erred element is a block-level element (such as |
381 |
|
|
<code>div</code> or <code>h<var>n</var></code>)</dt> |
382 |
|
|
<dd><p>Though some elements such as <code>div</code>, |
383 |
|
|
<code>li</code>, and <code>td</code> allow |
384 |
|
|
<em>either one</em> of block-level or inline-level content |
385 |
|
|
is allowed. If there is a block-level content, |
386 |
|
|
any inline-level content must be put |
387 |
|
|
in e.g. paragraph element such as <code>p</code>.</p></dd> |
388 |
|
|
<dt>If the erred element is the root <code>html</code> element</dt> |
389 |
|
|
<dd><p>In an XHTML document, the root <code>html</code> |
390 |
|
|
element must have an <code>xmlns</code> attribute |
391 |
|
|
whose value is set to |
392 |
|
|
<code>http://www.w3.org/1999/xhtml</code>.</p></dd> |
393 |
|
|
</dl> |
394 |
|
|
</p> |
395 |
|
|
</div> |
396 |
|
|
|
397 |
wakaba |
1.2 |
</section> |
398 |
|
|
|
399 |
wakaba |
1.3 |
<section id="attribute-errors"> |
400 |
|
|
<h2>Attribute Errors</h2> |
401 |
|
|
|
402 |
|
|
<div class="section attribute-error" id="attribute-missing"><h3>Required attribute <code><var>$0</var></code> |
403 |
|
|
is not specified.</h3> |
404 |
|
|
<p>A required attribute is not specified. The document |
405 |
|
|
is non-conforming.</p> |
406 |
|
|
|
407 |
|
|
<p>Some attribute is defined as <i>required</i>. |
408 |
|
|
For example, any <code>img</code> element must have |
409 |
|
|
<code>alt</code> and <code>src</code> attributes specified. |
410 |
|
|
Without required attributes specified, user agents |
411 |
|
|
cannot provide the full functionality of the element |
412 |
|
|
to the user.</p> |
413 |
|
|
</div> |
414 |
|
|
|
415 |
|
|
<div class="section attribute-error" id="in-HTML:xml:lang"><h3>The <code>xml:lang</code> attribute is not |
416 |
|
|
allowed in HTML document.</h3> |
417 |
|
|
<p>The <code>xml:lang</code> attribute is not allowed in |
418 |
|
|
HTML document. The document is non-conforming.</p> |
419 |
|
|
|
420 |
wakaba |
1.4 |
<p>The <code>lang</code> attribute in the <code>null</code> |
421 |
|
|
namespace for HTML elements is defined as conforming <em>only</em> for |
422 |
wakaba |
1.3 |
XML document.</p> |
423 |
|
|
|
424 |
|
|
<p>To specify natural language information in HTML document, |
425 |
|
|
use <code>lang</code> attribute instead.</p> |
426 |
|
|
<!-- @@ ISSUE: xml:lang in non-HTML element in DOM5 HTML created |
427 |
|
|
from an HTML document? --> |
428 |
|
|
</div> |
429 |
|
|
|
430 |
|
|
<div class="section attribute-error" id="in-XML:charset"><h3>The <code>charset</code> attribute is not |
431 |
|
|
allowed in XML document.</h3> |
432 |
|
|
<p>The <code>charset</code> attribute of a |
433 |
|
|
<code>meta</code> element is not allowed in XML document. |
434 |
|
|
The document is non-conforming.</p> |
435 |
|
|
|
436 |
|
|
<p>To specify the character encoding used for serialization, |
437 |
|
|
if necessary, use XML declaration instead: |
438 |
|
|
<pre class="xml example"> |
439 |
|
|
<code><?xml version="1.0" encoding="<var>encoding-name</var>"?></code></pre> |
440 |
|
|
</p> |
441 |
|
|
</div> |
442 |
|
|
|
443 |
|
|
<div class="section attribute-error" id="in-XML:lang"><h3>The <code>lang</code> attribute is not |
444 |
|
|
allowed in XML document.</h3> |
445 |
|
|
<p>The HTML <code>lang</code> attribute is not allowed in |
446 |
|
|
XML document. The document is non-conforming.</p> |
447 |
|
|
|
448 |
|
|
<p>The <code>lang</code> attribute in <code>null</code> |
449 |
wakaba |
1.4 |
namespace for HTML elements is defined as conforming <em>only</em> for |
450 |
wakaba |
1.3 |
HTML document.</p> |
451 |
|
|
|
452 |
|
|
<p>To specify natural language information in XML document, |
453 |
|
|
use <code>xml:lang</code> attribute instead.</p> |
454 |
|
|
</div> |
455 |
|
|
|
456 |
|
|
<div class="section attribute-error" id="in-XML:xmlns"><h3>The <code>xmlns</code> attribute |
457 |
|
|
in the <code>null</code> namespace is not allowed in |
458 |
|
|
XHTML document. The document is non-conforming.</h3> |
459 |
|
|
<p>The <code>xmlns</code> attribute in the <code>null</code> |
460 |
|
|
namespace is not allowed in XHTML document.</p> |
461 |
|
|
|
462 |
|
|
<p>This error should not occur in conformance-checking |
463 |
|
|
static documents.</p> |
464 |
|
|
</div> |
465 |
|
|
|
466 |
|
|
</section> |
467 |
|
|
|
468 |
wakaba |
1.2 |
<section id="attribute-value-errors"> |
469 |
|
|
<h2>Attribute Value Errors</h2> |
470 |
|
|
|
471 |
wakaba |
1.3 |
<div class="section attribute-value-error" id="enumerated:invalid"><h3>This attribute only allow a limited set of |
472 |
wakaba |
1.2 |
values and the specified value is not one of them.</h3></div> |
473 |
|
|
|
474 |
wakaba |
1.3 |
<div class="section attribute-value-error" id="duplicate-ID"><h3>This identifier has already been |
475 |
|
|
assigned to another element.</h3></div> |
476 |
|
|
|
477 |
wakaba |
1.4 |
<div class="section attribute-value-error" id="link-type:bad-context"><h3>The link type <code><var>$0</var></code> |
478 |
|
|
cannot be specified for this element.</h3> |
479 |
|
|
<p>The specified link type cannot be used for the element. |
480 |
|
|
The document is non-conforming.</p> |
481 |
|
|
|
482 |
|
|
<p>Link types are associated with limited set of elements. |
483 |
|
|
They cannot be used with other elements.</p> |
484 |
|
|
|
485 |
|
|
<p>For example, link type <code>bookmark</code> |
486 |
|
|
can be used with <code>a</code> or <code>area</code> element, |
487 |
|
|
while it cannot be used with <code>link</code> element.</p> |
488 |
|
|
</div> |
489 |
|
|
|
490 |
|
|
<div class="section attribute-value-error" id="link-type:non-conforming"><h3>The link type <code><var>$0</var></code> |
491 |
|
|
is non-conforming.</h3> |
492 |
|
|
<p>The specified link type is non-conforming. The entire document |
493 |
|
|
is non-conforming.</p> |
494 |
|
|
|
495 |
|
|
<p>For example, in place of non-conforming link type <code>copyright</code> |
496 |
|
|
you must use link type <code>license</code>.</p> |
497 |
|
|
</div> |
498 |
|
|
|
499 |
wakaba |
1.3 |
<div class="section attribute-value-error" id="reserved-browsing-context-name"><h3>This browsing context name is reserved.</h3></div> |
500 |
|
|
|
501 |
wakaba |
1.2 |
</section> |
502 |
|
|
|
503 |
wakaba |
1.4 |
<section id="attribute-value-warnings"> |
504 |
|
|
<h2>Attribute Value Warnings</h2> |
505 |
|
|
|
506 |
|
|
<div class="section attribute-value-warning should" id="s:link-type:proposed"><h3>Link type <code><var>$0</var></code> |
507 |
|
|
is proposed but not accepted yet; it <em>should not</em> be |
508 |
|
|
used until it has been accepted.</h3> |
509 |
|
|
<p>The link type is in the <i>proposed</i> status; it |
510 |
|
|
<em>should not</em> be used until it has been |
511 |
|
|
accepted.</p> |
512 |
|
|
|
513 |
|
|
<p><strong>Warning</strong>: The data served to the |
514 |
|
|
conforming checker might be out of date; it might have already |
515 |
|
|
been accepted or rejected, depending on which the document |
516 |
|
|
might be conforming or non-conforming. See WHATWG Wiki |
517 |
|
|
for the latest information.</p> |
518 |
|
|
</div> |
519 |
|
|
|
520 |
|
|
</section> |
521 |
|
|
|
522 |
wakaba |
1.2 |
<section id="table-model-errors"> |
523 |
|
|
<h2>Table Model Errors</h2> |
524 |
|
|
|
525 |
wakaba |
1.3 |
<div class="section table-model-error" id="table:colspan-creates-column-with-no-anchored-cell"><h3>This <code>colspan</code> attribute |
526 |
|
|
results in creating a table column that does not contain |
527 |
|
|
any cell anchored to it.</h3></div> |
528 |
|
|
|
529 |
wakaba |
1.2 |
<div class="section table-model-error" id="table:no-cell-in-last-row"><h3>The table has no cell (<code>td</code> or |
530 |
|
|
<code>th</code>) in the last row.</h3></div> |
531 |
|
|
|
532 |
|
|
</section> |
533 |
|
|
|
534 |
|
|
<section id="imt-warnings"> |
535 |
|
|
<h2>Internet Media Type Warnings</h2> |
536 |
wakaba |
1.1 |
|
537 |
wakaba |
1.2 |
<div class="section should" id="s:IMT:obsolete-subtype"><h3>An <em>obsolete</em> subtype is used.</h3></div> |
538 |
|
|
|
539 |
|
|
<div class="section should" id="s:IMT:private-subtype"><h3>A private (<code>x-</code> or <code>x.</code>) |
540 |
|
|
subtype is used.</h3></div> |
541 |
|
|
|
542 |
|
|
<div class="section should" id="s:IMT:unregistered-subtype"><h3>The subtype is not registered to IANA.</h3></div> |
543 |
|
|
|
544 |
|
|
</section> |
545 |
|
|
|
546 |
|
|
<section id="uri-errors"> |
547 |
|
|
<h2>URI (or IRI) Errors</h2> |
548 |
|
|
|
549 |
wakaba |
1.5 |
<div class="section must" id="m:URI::syntax-error"><h3>This string is syntactically not an IRI.</h3></div> |
550 |
wakaba |
1.2 |
|
551 |
|
|
</section> |
552 |
|
|
|
553 |
wakaba |
1.3 |
<section id="uri-warnings"> |
554 |
|
|
<h2>URI (or IRI) Warnings</h2> |
555 |
|
|
|
556 |
|
|
<div class="section should" id="s:URI::dot-segment"><h3>Dot-segment (<code>.</code> or |
557 |
|
|
<code>..</code>) should not occur in an absolute reference.</h3> |
558 |
|
|
<p>Dot-segment (<code>.</code> or <code>..</code>) should |
559 |
|
|
not occur in an absolute reference.</p> |
560 |
|
|
|
561 |
|
|
<p>In relative references, dot-segments are used to represent |
562 |
|
|
the current (<code>.</code>) or the parent (<code>..</code>) |
563 |
|
|
hierarchy of the path. Though they are also allowed |
564 |
|
|
in absolute references, it should be resolved to the |
565 |
|
|
canonical form before it has been published.</p> |
566 |
|
|
</div> |
567 |
wakaba |
1.2 |
|
568 |
|
|
<div class="section should" id="s:URI::empty-path"><h3>This IRI should explicitly end with |
569 |
|
|
<code>/</code>.</h3></div> |
570 |
wakaba |
1.1 |
|
571 |
wakaba |
1.4 |
<div class="section should" id="s:URI::lowercase-hexadecimal-digit"><h3>Hexadecimal digit in percent-encoding |
572 |
|
|
should be in lowercase.</h3> |
573 |
wakaba |
1.5 |
<p>The hexadecimal digit in percent-encoding string in the IRI |
574 |
wakaba |
1.4 |
is in lowercase. Though the IRI <em>is</em> conforming, |
575 |
|
|
it should be in uppercase.</p> |
576 |
|
|
</div> |
577 |
|
|
|
578 |
|
|
<div class="section should" id="s:URI::percent-encoded-unreserved"><h3>An unreserved character is |
579 |
|
|
percent-encoded.</h3> |
580 |
|
|
<p>An unreserved character is percent-encoded in the IRI. |
581 |
|
|
Though it <em>is</em> conforming, it should be in the |
582 |
|
|
decoded (or bare) form.</p> |
583 |
|
|
</div> |
584 |
|
|
|
585 |
wakaba |
1.1 |
</section> |
586 |
|
|
|
587 |
|
|
<section id="unsupported-messages"> |
588 |
|
|
<h2><i>Unsupported</i> Messages</h2> |
589 |
|
|
|
590 |
|
|
<div class="section unsupported" id="unsupported:attribute"><h3>This attribute is not supported by the |
591 |
|
|
conformance checker; <em>it might or might not be conforming</em>.</h3> |
592 |
|
|
<p>The conformant checker does not support the attribute. |
593 |
|
|
It cannot determine whether the document is conforming or not.</p> |
594 |
|
|
</div> |
595 |
|
|
|
596 |
|
|
<div class="section unsupported" id="unsupported:element"><h3>This element is not supported by the |
597 |
|
|
conformance checker; <em>it might or might not be conforming</em>.</h3> |
598 |
|
|
<p>The conformant checker does not support the element. |
599 |
|
|
It cannot determine whether the document is conforming or not.</p> |
600 |
|
|
</div> |
601 |
|
|
|
602 |
wakaba |
1.4 |
<div class="section unsupported" id="unsupported:link-type"><h3>The link type <code><var>$0</var></code> is not |
603 |
|
|
standardized or registered at the time of the release of the conformance |
604 |
|
|
checker; <em>it is non-conforming unless it has now been |
605 |
|
|
registered</em>.</h3> |
606 |
wakaba |
1.1 |
<p>The <code>rel</code> attribute is defined as a list of link types. |
607 |
|
|
Some common link types are defined in the HTML5 specification. |
608 |
|
|
Additional link types can be registered to the WHATWG Wiki. |
609 |
|
|
use of any other link type is non-conforming.</p> |
610 |
|
|
|
611 |
|
|
<p>The specified link type is not part of the standard or registry |
612 |
|
|
when the database used by the conformance cheker is created. |
613 |
|
|
The link type might have been added to the registry since then. |
614 |
|
|
In such case it might be conforming. Otherwise, the |
615 |
|
|
document is non-conforming.</p> |
616 |
|
|
</div> |
617 |
|
|
|
618 |
wakaba |
1.4 |
<div class="section unsupported" id="unsupported:event-handler"><h3>Conformance checking for event handler attribute |
619 |
|
|
is not supported; <em>it might or might not be conforming.</em></h3></div> |
620 |
|
|
|
621 |
|
|
<div class="section unsupported" id="unsupported:language-tag"><h3>Conformance checking for language tag |
622 |
|
|
is not supported; <em>it might or might not be conforming.</em></h3></div> |
623 |
|
|
|
624 |
|
|
<div class="section unsupported" id="unsupported:media-query"><h3>Conformance checking for media query |
625 |
|
|
is not supported; <em>it might or might not be conforming.</em></h3></div> |
626 |
|
|
|
627 |
|
|
<div class="section unsupported" id="unsupported:script"><h3>Conformance checking for script |
628 |
|
|
language <code><var>$0</var></code> is not supported; |
629 |
|
|
<em>it might or might not be conforming.</em></h3></div> |
630 |
|
|
|
631 |
|
|
<div class="section unsupported" id="unsupported:style"><h3>Conformance checking for style |
632 |
|
|
language <code><var>$0</var></code> is not supported; |
633 |
|
|
<em>it might or might not be conforming.</em></h3></div> |
634 |
|
|
|
635 |
wakaba |
1.1 |
</section> |
636 |
|
|
|
637 |
wakaba |
1.3 |
|
638 |
wakaba |
1.2 |
|
639 |
wakaba |
1.1 |
<section id="license"> |
640 |
|
|
<h2>License of This Document</h2> |
641 |
|
|
|
642 |
|
|
<p>Copyright 2007 <a href="http://suika.fam.cx/~wakaba/who?">Wakaba</a></p> |
643 |
|
|
<p>This library is free software; you can redistribute it |
644 |
|
|
and/or modify it under the same terms as Perl itself.</p> |
645 |
|
|
</section> |
646 |
|
|
|
647 |
wakaba |
1.5 |
<!-- $Date: 2007/07/16 13:56:26 $ --> |
648 |
wakaba |
1.1 |
</body> |
649 |
|
|
</html> |