| 56 |
</p> |
</p> |
| 57 |
</div> |
</div> |
| 58 |
|
|
| 59 |
|
<div class="section tokenize-error" id="bare-stago"><h3>A <code><</code> character is not followed |
| 60 |
|
by tag name or by a <code>!</code> character.</h3> |
| 61 |
|
<p>A <code><</code> (<code>U+003C</code> <code class="charname">LESS-THAN |
| 62 |
|
SIGN</code>) character which is not part of any markup appears |
| 63 |
|
in the input stream.</p> |
| 64 |
|
|
| 65 |
|
<p>The <code><</code> character as a data character must |
| 66 |
|
be escaped as: |
| 67 |
|
<pre class="html example"> |
| 68 |
|
<code><lt;</code></pre> |
| 69 |
|
</p> |
| 70 |
|
</div> |
| 71 |
|
|
| 72 |
<div class="section tokenize-error" id="bare-nero"><h3>The decimal representation of the code position |
<div class="section tokenize-error" id="bare-nero"><h3>The decimal representation of the code position |
| 73 |
of a character must be specified after <code>&#</code>.</h3> |
of a character must be specified after <code>&#</code>.</h3> |
| 74 |
<p>An <code>&</code> (<code>U+0026</code> |
<p>An <code>&</code> (<code>U+0026</code> |
| 122 |
</p> |
</p> |
| 123 |
</div> |
</div> |
| 124 |
|
|
| 125 |
|
<div class="section tokenize-error" id="dash-in-comment"><h3>There is a <code>--</code> sequence |
| 126 |
|
in a comment.</h3> |
| 127 |
|
<p>There is a <code>-</code> (<code>U+002D</code> |
| 128 |
|
<code class="charname">HYPHEN-MINUS</code>) character |
| 129 |
|
at the end of the comment or a <code>--</code> sequence |
| 130 |
|
in the comment. The document is non-conforming.</p> |
| 131 |
|
|
| 132 |
|
<p>Comments cannot contain a string <code>--</code>, as in XML. |
| 133 |
|
Unlike SGML, there cannot be more than one comments |
| 134 |
|
(where <i>comment</i> is an SGML term) in the comment |
| 135 |
|
declaration.</p> |
| 136 |
|
</div> |
| 137 |
|
|
| 138 |
<div class="section tokenize-error" id="duplicate-attribute"><h3>There are two attributes with same name.</h3> |
<div class="section tokenize-error" id="duplicate-attribute"><h3>There are two attributes with same name.</h3> |
| 139 |
<p>There are more than one attributes with the same |
<p>There are more than one attributes with the same |
| 140 |
name in a tag. The document is non-conforming.</p> |
name in a tag. The document is non-conforming.</p> |
| 158 |
no effect in HTML.</p> |
no effect in HTML.</p> |
| 159 |
</div> |
</div> |
| 160 |
|
|
| 161 |
|
|
| 162 |
|
<div class="section tokenize-error" id="pio"><h3>Processing instruction |
| 163 |
|
(<code><?<var>...</var>?></code>) cannot be used.</h3> |
| 164 |
|
<p>Processing instructions (<code><?<var>...</var>?></code>), |
| 165 |
|
including XML declaration (<code><?xml <var>...</var>?></code>) |
| 166 |
|
and XML style sheet <abbr title="processing instruction">PI</abbr> |
| 167 |
|
(<code><xml-stylesheet <var>...</var>?></code>), are not allowed |
| 168 |
|
in the HTML syntax. The document is non-conforming.</p> |
| 169 |
|
|
| 170 |
|
<p>If it is necessary to embed a processing instruction |
| 171 |
|
in the HTML document, you must use the XML syntax instead.</p> |
| 172 |
|
|
| 173 |
|
<p>In the HTML syntax, XML declaration is not necessary.</p> |
| 174 |
|
|
| 175 |
|
<p>Instead of XML style sheet, |
| 176 |
|
<abbr title="processing instruction">PI</abbr>s, you must |
| 177 |
|
use the HTML <code>link</code> element whose <code>rel</code> |
| 178 |
|
attribute is set to <code>stylesheet</code> (or <code>alternate |
| 179 |
|
stylesheet</code> for an aleternate style sheet).</p> |
| 180 |
|
|
| 181 |
|
<p>Web browsers will parse processing instructions as bogus |
| 182 |
|
comments. Some legacy Web browsers, such as IE:mac and |
| 183 |
|
some mobile browsers, will display processing instructions |
| 184 |
|
as string.</p> |
| 185 |
|
</div> |
| 186 |
|
|
| 187 |
</section> |
</section> |
| 188 |
|
|
| 189 |
<section id="html5-parse-errors"> |
<section id="html5-parse-errors"> |
| 196 |
The document is non-conforming.</p> |
The document is non-conforming.</p> |
| 197 |
</div> |
</div> |
| 198 |
|
|
| 199 |
|
<div class="section parse-error" id="DOCTYPE-in-the-middle"><h3>A <code>DOCTYPE</code> appears after any |
| 200 |
|
element or data character has been seen.</h3> |
| 201 |
|
<p>A <code>DOCTYPE</code> appears after any element or data character |
| 202 |
|
has been seen. The document is non-conforming.</p> |
| 203 |
|
|
| 204 |
|
<p>The <code>DOCTYPE</code> must be placed before any |
| 205 |
|
tag, reference, or data character. Only white space characters |
| 206 |
|
and comments can be inserted before the <code>DOCTYPE</code>.</p> |
| 207 |
|
</div> |
| 208 |
|
|
| 209 |
|
<div class="section parse-error" id="in-a:a"><h3>Anchor cannot be nested.</h3> |
| 210 |
|
<p>HTML <code>a</code> elements cannot be nested. |
| 211 |
|
The document is non-conforming.</p> |
| 212 |
|
|
| 213 |
|
<p>In the HTML syntax, a start tag of the <code>a</code> |
| 214 |
|
implies the end tag of any opening <code>a</code> element.</p> |
| 215 |
|
</div> |
| 216 |
|
|
| 217 |
|
<div class="section parse-error" id="in-body"><h3>Tag <code><<var>$0</var>></code> |
| 218 |
|
is not allowed in <code>body</code>.</h3> |
| 219 |
|
<p>The start or end tag of an element, which |
| 220 |
|
cannot be a descendant of <code>body</code> element, appears |
| 221 |
|
in the input stream while the <code>body</code> element has been opened. |
| 222 |
|
The document is non-conforming.</p> |
| 223 |
|
</div> |
| 224 |
|
|
| 225 |
<div class="section parse-error" id="in-table"><h3>Tag <code><<var>$0</var>></code> |
<div class="section parse-error" id="in-table"><h3>Tag <code><<var>$0</var>></code> |
| 226 |
is not allowed in <code>table</code>.</h3> |
is not allowed in <code>table</code>.</h3> |
| 227 |
<p>The start or end tag of an element appears in <code>table</code>. |
<p>The start or end tag of an element, which |
| 228 |
The document is non-conforming.</p> |
cannot be a child of <code>table</code> element, appears |
| 229 |
|
in the input stream while the <code>table</code> element has been opened |
| 230 |
|
but no other element has been opened. The document is non-conforming.</p> |
| 231 |
|
|
| 232 |
<p>In <code>table</code>, only table related elements |
<p>In <code>table</code>, only table related elements |
| 233 |
are allowed; any other element must be contained in |
are allowed; any other element must be contained in |
| 295 |
</div> |
</div> |
| 296 |
|
|
| 297 |
<div class="section parse-error" id="unmatched-end-tag"><h3>Element <code><var>$0</var></code> is not |
<div class="section parse-error" id="unmatched-end-tag"><h3>Element <code><var>$0</var></code> is not |
| 298 |
opened.</h3></div> |
opened.</h3> |
| 299 |
|
<p>An end tag appears though no element with the same name |
| 300 |
|
has been opened. The document is non-conforming.</p> |
| 301 |
|
|
| 302 |
|
<p>For any end tag in HTML document, there must be a |
| 303 |
|
corresponding start tag.</p> |
| 304 |
|
</div> |
| 305 |
|
|
| 306 |
</section> |
</section> |
| 307 |
|
|
| 417 |
<p>The <code>xml:lang</code> attribute is not allowed in |
<p>The <code>xml:lang</code> attribute is not allowed in |
| 418 |
HTML document. The document is non-conforming.</p> |
HTML document. The document is non-conforming.</p> |
| 419 |
|
|
| 420 |
<p>The <code>xml:lang</code> attribute in <code>null</code> |
<p>The <code>lang</code> attribute in the <code>null</code> |
| 421 |
namespace for HTML elements is defined as conforming only for |
namespace for HTML elements is defined as conforming <em>only</em> for |
| 422 |
XML document.</p> |
XML document.</p> |
| 423 |
|
|
| 424 |
<p>To specify natural language information in HTML document, |
<p>To specify natural language information in HTML document, |
| 446 |
XML document. The document is non-conforming.</p> |
XML document. The document is non-conforming.</p> |
| 447 |
|
|
| 448 |
<p>The <code>lang</code> attribute in <code>null</code> |
<p>The <code>lang</code> attribute in <code>null</code> |
| 449 |
namespace for HTML elements is defined as conforming only for |
namespace for HTML elements is defined as conforming <em>only</em> for |
| 450 |
HTML document.</p> |
HTML document.</p> |
| 451 |
|
|
| 452 |
<p>To specify natural language information in XML document, |
<p>To specify natural language information in XML document, |
| 474 |
<div class="section attribute-value-error" id="duplicate-ID"><h3>This identifier has already been |
<div class="section attribute-value-error" id="duplicate-ID"><h3>This identifier has already been |
| 475 |
assigned to another element.</h3></div> |
assigned to another element.</h3></div> |
| 476 |
|
|
| 477 |
|
<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 |
<div class="section attribute-value-error" id="reserved-browsing-context-name"><h3>This browsing context name is reserved.</h3></div> |
<div class="section attribute-value-error" id="reserved-browsing-context-name"><h3>This browsing context name is reserved.</h3></div> |
| 500 |
|
|
| 501 |
</section> |
</section> |
| 502 |
|
|
| 503 |
|
<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 |
<section id="table-model-errors"> |
<section id="table-model-errors"> |
| 523 |
<h2>Table Model Errors</h2> |
<h2>Table Model Errors</h2> |
| 524 |
|
|
| 546 |
<section id="uri-errors"> |
<section id="uri-errors"> |
| 547 |
<h2>URI (or IRI) Errors</h2> |
<h2>URI (or IRI) Errors</h2> |
| 548 |
|
|
| 549 |
<div class="section must" id="m:URI::syntax-error"><h3>This string is not an IRI syntactically.</h3></div> |
<div class="section must" id="m:URI::syntax-error"><h3>This string is syntactically not an IRI.</h3></div> |
| 550 |
|
|
| 551 |
</section> |
</section> |
| 552 |
|
|
| 568 |
<div class="section should" id="s:URI::empty-path"><h3>This IRI should explicitly end with |
<div class="section should" id="s:URI::empty-path"><h3>This IRI should explicitly end with |
| 569 |
<code>/</code>.</h3></div> |
<code>/</code>.</h3></div> |
| 570 |
|
|
| 571 |
|
<div class="section should" id="s:URI::lowercase-hexadecimal-digit"><h3>Hexadecimal digit in percent-encoding |
| 572 |
|
should be in lowercase.</h3> |
| 573 |
|
<p>The hexadecimal digit in percent-encoding string in the IRI |
| 574 |
|
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 |
</section> |
</section> |
| 586 |
|
|
| 587 |
<section id="unsupported-messages"> |
<section id="unsupported-messages"> |
| 599 |
It cannot determine whether the document is conforming or not.</p> |
It cannot determine whether the document is conforming or not.</p> |
| 600 |
</div> |
</div> |
| 601 |
|
|
| 602 |
<div class="section unsupported" id="unsupported:link-type"><h3>The link type <code>$0</code> is not standardized |
<div class="section unsupported" id="unsupported:link-type"><h3>The link type <code><var>$0</var></code> is not |
| 603 |
or registered at the time of the release of the conformance checker; |
standardized or registered at the time of the release of the conformance |
| 604 |
<em>it is non-conforming unless it has now been registered</em>.</h3> |
checker; <em>it is non-conforming unless it has now been |
| 605 |
|
registered</em>.</h3> |
| 606 |
<p>The <code>rel</code> attribute is defined as a list of link types. |
<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. |
Some common link types are defined in the HTML5 specification. |
| 608 |
Additional link types can be registered to the WHATWG Wiki. |
Additional link types can be registered to the WHATWG Wiki. |
| 615 |
document is non-conforming.</p> |
document is non-conforming.</p> |
| 616 |
</div> |
</div> |
| 617 |
|
|
| 618 |
|
<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 |
</section> |
</section> |
| 636 |
|
|
| 637 |
|
|