| 11 |
<body> |
<body> |
| 12 |
<h1>Description of Errors</h1> |
<h1>Description of Errors</h1> |
| 13 |
|
|
| 14 |
|
<section id="html5-character-encoding"> |
| 15 |
|
<h2>HTML5 Character Encoding Errors</h2> |
| 16 |
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|
| 17 |
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<d:item name="character encoding" class="format-charset must" level="m"> |
| 18 |
|
<d:message xml:lang="en">Character encoding <code><var>$0</var></code> |
| 19 |
|
is not allowed for <abbr>HTML</abbr> document.</d:message> |
| 20 |
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<d:desc xml:lang="en"> |
| 21 |
|
<p>The character encoding used for the document is not allowed |
| 22 |
|
for <abbr>HTML</abbr> document. The document is non‐conforming.</p> |
| 23 |
|
</d:desc> |
| 24 |
|
</d:item> |
| 25 |
|
|
| 26 |
|
<d:item name="character encoding" class="format-charset should" |
| 27 |
|
level="s"> |
| 28 |
|
<d:message xml:lang="en">Character encoding <code><var>$0</var></code> |
| 29 |
|
should not be used for <abbr>HTML</abbr> document.</d:message> |
| 30 |
|
<d:desc xml:lang="en"> |
| 31 |
|
<p>The character encoding used for the document is not recommended |
| 32 |
|
for <abbr>HTML</abbr> document. The document is non‐conforming |
| 33 |
|
unless there is any good reason to use that encoding.</p> |
| 34 |
|
</d:desc> |
| 35 |
|
</d:item> |
| 36 |
|
|
| 37 |
|
<d:item name="character encoding" class="format-charset warning" |
| 38 |
|
level="w"> |
| 39 |
|
<d:message xml:lang="en">Use of UTF-8 is encouraged.</d:message> |
| 40 |
|
<d:desc xml:lang="en"> |
| 41 |
|
<p>Use of UTF-8 as the character encoding of the document is encouraged, |
| 42 |
|
though the use of another character encoding is conforming.</p> |
| 43 |
|
</d:desc> |
| 44 |
|
</d:item> |
| 45 |
|
|
| 46 |
|
<d:item name="character encoding" class="format-charset unsupported" |
| 47 |
|
level="unsupported"> |
| 48 |
|
<d:message xml:lang="en">Conformance for character encoding requirements |
| 49 |
|
cannot be checked.</d:message> |
| 50 |
|
<d:desc xml:lang="en"> |
| 51 |
|
<p>The conformance checker cannot detect whether the input document |
| 52 |
|
met the requirements on character encoding, since the document |
| 53 |
|
is not inputed as a serialized byte sequence. The document is |
| 54 |
|
not conforming if it is not encoded in an appropriate character |
| 55 |
|
encoding with appropriate labeling.</p> |
| 56 |
|
</d:desc> |
| 57 |
|
</d:item> |
| 58 |
|
|
| 59 |
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<d:item name="no character encoding declaration" class="format-charset error" |
| 60 |
|
level="m"> |
| 61 |
|
<d:message xml:lang="en">There is no character encoding |
| 62 |
|
declaration.</d:message> |
| 63 |
|
<d:desc xml:lang="en"> |
| 64 |
|
<p>The document does not contain a character encoding |
| 65 |
|
declaration. Unless the character encoding is explicitly |
| 66 |
|
specified in lower‐level protocol, e.g. in <abbr>HTTP</abbr>, |
| 67 |
|
or is implied by <abbr>BOM</abbr>, there must be a character |
| 68 |
|
encoding declaration. The document is non‐conforming.</p> |
| 69 |
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|
| 70 |
|
<p>The long character encoding declaration syntax |
| 71 |
|
<code class="html bad example"><meta http-equiv="Content-Type" content="text/html; charset=<var>charset-name</var>"></code> |
| 72 |
|
is obsolete. The new syntax is:</p> |
| 73 |
|
<pre class="html example"><code><meta charset="<var>charset-name</var>"></code></pre> |
| 74 |
|
|
| 75 |
|
<p>Note that the <code>encoding</code> declaration in <abbr>XML</abbr> |
| 76 |
|
declaration has no effect for <abbr>HTML</abbr> document.</p> |
| 77 |
|
</d:desc> |
| 78 |
|
</d:item> |
| 79 |
|
|
| 80 |
|
<d:item name="non ascii superset" class="format-charset error" |
| 81 |
|
level="m"> |
| 82 |
|
<d:message xml:lang="en">No character encoding metadata is found |
| 83 |
|
in lower‐level protocol nor is there <abbr>BOM</abbr>, while |
| 84 |
|
character encoding <code><var>$0</var></code> |
| 85 |
|
is not a superset of <abbr>ASCII</abbr>.</d:message> |
| 86 |
|
<d:desc xml:lang="en"> |
| 87 |
|
<p>The document is not labeled with character encoding name |
| 88 |
|
in lower‐level protocol, e.g. in <abbr>HTTP</abbr>, and |
| 89 |
|
the document is not begin with <abbr>BOM</abbr>. In addition, |
| 90 |
|
the character encoding of the document is not a superset of |
| 91 |
|
<abbr>ASCII</abbr>. The document is non‐conforming.</p> |
| 92 |
|
|
| 93 |
|
<p>Unless there is a <abbr>BOM</abbr>, the character encoding |
| 94 |
|
for the document must be specified in e.g. <abbr>HTTP</abbr>‐level, |
| 95 |
|
as:</p> |
| 96 |
|
<pre class="http example"><code>Content-Type: text/html; charset=<var>charset-name</var></code></pre> |
| 97 |
|
|
| 98 |
|
<p>Existence of <abbr>HTML</abbr> character encoding declaration, i.e. |
| 99 |
|
<code class="html example"><meta charset="<var>charset-name</var>"></code>, |
| 100 |
|
does not allow to omit <code>charset</code> parameter |
| 101 |
|
for <abbr>HTML</abbr> document encoded in non‐<abbr>ASCII</abbr> |
| 102 |
|
compatible encoding.</p> |
| 103 |
|
|
| 104 |
|
<p>Character encodings <code>Shift_JIS</code>, <code>Windows-31J</code>, |
| 105 |
|
and <code>ISO-2022-JP</code> are <em>not</em> a superset of |
| 106 |
|
<abbr>ASCII</abbr> for the purpose of <abbr>HTML</abbr> conformance.</p> |
| 107 |
|
</d:desc> |
| 108 |
|
</d:item> |
| 109 |
|
|
| 110 |
|
<d:item name="charset label detected" class="format-charset warning" |
| 111 |
|
level="w"> |
| 112 |
|
<d:message xml:lang="en">While parsing the document as |
| 113 |
|
<code><var>$0</var></code>, a character encoding declaration specifying |
| 114 |
|
character encoding as <code><var>$1</var></code> is found. The document |
| 115 |
|
is reparsed.</d:message> |
| 116 |
|
<d:desc xml:lang="en"> |
| 117 |
|
<p>While parsing a document in a character encoding, |
| 118 |
|
a character encoding declaration which declares the character |
| 119 |
|
encoding of the document as another character encoding is found. |
| 120 |
|
The occurence of this warning itself does not make the document |
| 121 |
|
non‐conforming. However, the failure of the first attempt to |
| 122 |
|
to detect the character encoding might be the result of non‐conformance |
| 123 |
|
of the document.</p> |
| 124 |
|
|
| 125 |
|
<p>The document will be reparsed from the beginning. Some error |
| 126 |
|
or warning might be reported again.</p> |
| 127 |
|
|
| 128 |
|
<p>These are suggestions to avoid this warning:</p> |
| 129 |
|
<ul> |
| 130 |
|
<li>Specify <code>charset</code> parameter in the <code>Content-Type</code> |
| 131 |
|
field in the <abbr>HTTP</abbr> header, as: |
| 132 |
|
<pre class="HTTP example"><code>Content-Type: text/html; charset="<var>charset-name</var>"</code></pre></li> |
| 133 |
|
<li>Put the character encoding declaration |
| 134 |
|
(<code class="html example"><meta charset="<var>charset-name</var>"></code>) |
| 135 |
|
just after <code class="html example"><head></code> start tag.</li> |
| 136 |
|
<li>Use <code>UTF-8</code>.</li> |
| 137 |
|
</ul> |
| 138 |
|
</d:desc> |
| 139 |
|
</d:item> |
| 140 |
|
</section> |
| 141 |
|
|
| 142 |
<section id="html5-tokenize-error"> |
<section id="html5-tokenize-error"> |
| 143 |
<h2>HTML5 Parse Errors in Tokenization Stage</h2> |
<h2>HTML5 Parse Errors in Tokenization Stage</h2> |
| 144 |
|
|
| 156 |
</d:desc> |
</d:desc> |
| 157 |
</d:item> |
</d:item> |
| 158 |
|
|
| 159 |
|
<d:item name="after body" |
| 160 |
|
class="parse-error"> |
| 161 |
|
<d:message xml:lang="en">Tag <code><<var>$0</var>></code> |
| 162 |
|
is not allowed after the end tag <code></body></code>.</d:message> |
| 163 |
|
<d:desc xml:lang="en"> |
| 164 |
|
<p>The start or end tag of an element appears after the |
| 165 |
|
<code>body</code> element has been closed. The document is |
| 166 |
|
non-conforming.</p> |
| 167 |
|
|
| 168 |
|
<p>Any content of the document other than <code>head</code> |
| 169 |
|
contents and comments must be put into the <code>body</code> |
| 170 |
|
element.</p> |
| 171 |
|
</d:desc> |
| 172 |
|
</d:item> |
| 173 |
|
|
| 174 |
<d:item name="bare ero" |
<d:item name="bare ero" |
| 175 |
class="tokenize-error"> |
class="tokenize-error"> |
| 176 |
<d:message xml:lang="en">The <code>&</code> character must |
<d:message xml:lang="en">The <code>&</code> character must |
| 177 |
introduce a reference.</d:message> |
introduce a reference.</d:message> |
| 178 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 179 |
<p>An <code>&</code> (<code>U+0026</code> |
<p>An <code>&</code> character which |
|
<code class="charname">AMPERSAND</code>) character which |
|
| 180 |
is not part of any reference appears in the input stream. |
is not part of any reference appears in the input stream. |
| 181 |
The document is non-conforming.</p> |
The document is non‐conforming.</p> |
| 182 |
|
|
| 183 |
|
<p><em>Any <code>&</code> character in URI (or IRI) |
| 184 |
|
must be escaped as <code class="example">&amp;</code>.</em></p> |
| 185 |
|
|
| 186 |
<p>The <code>&</code> character must |
<p>The <code>&</code> character must |
| 187 |
be the first character of a reference: |
be the first character of a reference: |
| 188 |
<dl> |
<dl class="switch"> |
| 189 |
<dt>Named entity reference</dt> |
<dt>Named entity reference</dt> |
| 190 |
<dd><pre class="html example"><code>&<var>entity-name</var>;</code></pre> |
<dd><pre class="html example"><code>&<var>entity-name</var>;</code></pre> |
| 191 |
where <var>entity-name</var> is the name of the |
where <var>entity-name</var> is the name of the |
| 208 |
</d:desc> |
</d:desc> |
| 209 |
</d:item> |
</d:item> |
| 210 |
|
|
| 211 |
|
<d:item name="bare etago" |
| 212 |
|
class="tokenize-error"> |
| 213 |
|
<d:message xml:lang="en">A <code></</code> string is not followed |
| 214 |
|
by a tag name.</d:message><!-- </ EOF --> |
| 215 |
|
<d:desc xml:lang="en"> |
| 216 |
|
<p>There is a <code><</code> (<code>U+003C</code> |
| 217 |
|
<code class="charname">LESS-THAN SIGN</code>) character |
| 218 |
|
immediately followed by a <code>/</code> (<code>U+005F</code> |
| 219 |
|
<code>SOLIDUS</code>) character, which is not part |
| 220 |
|
of any end tag, in the input stream. The document |
| 221 |
|
is non-conforming.</p> |
| 222 |
|
|
| 223 |
|
<p>The <code></</code> sequence immediately followed |
| 224 |
|
by an <abbr title="End of file pseudo-character">EOF</abbr> is |
| 225 |
|
interpreted as a string data of <code></</code>.</p> |
| 226 |
|
|
| 227 |
|
<p>The <code></</code> sequence as string data must |
| 228 |
|
be escaped as: |
| 229 |
|
<pre class="html example"><code>&lt;/</code></pre> |
| 230 |
|
</p> |
| 231 |
|
</d:desc> |
| 232 |
|
</d:item> |
| 233 |
|
|
| 234 |
<d:item name="bare stago" |
<d:item name="bare stago" |
| 235 |
class="tokenize-error"> |
class="tokenize-error"> |
| 236 |
<d:message xml:lang="en">A <code><</code> character is not followed |
<d:message xml:lang="en">A <code><</code> character is not followed |
| 261 |
|
|
| 262 |
<p>The string <code>&#</code> must be the first two characters |
<p>The string <code>&#</code> must be the first two characters |
| 263 |
of a reference: |
of a reference: |
| 264 |
<dl> |
<dl class="switch"> |
| 265 |
<dt>Numeric character reference</dt> |
<dt>Numeric character reference</dt> |
| 266 |
<dd><pre class="html example"><code>&#<var>d</var>;</code></pre> |
<dd><pre class="html example"><code>&#<var>d</var>;</code></pre> |
| 267 |
where <var>d</var> is the decimal representation of |
where <var>d</var> is the decimal representation of |
| 302 |
</d:desc> |
</d:desc> |
| 303 |
</d:item> |
</d:item> |
| 304 |
|
|
| 305 |
|
<d:item name="bogus comment" |
| 306 |
|
class="tokenize-error"> |
| 307 |
|
<d:message xml:lang="en">String <code><!</code> is not followed |
| 308 |
|
by <code>--</code>.</d:message> |
| 309 |
|
<d:desc xml:lang="en"> |
| 310 |
|
<p>There is a <code><</code> (<code>U+003C</code> |
| 311 |
|
<code class="charname">LESS-THAN SIGN</code>) character |
| 312 |
|
followed by a <code>!</code> (<code>U+0021</code> |
| 313 |
|
<code class="charname">EXCLAMATION MARK</code>) character, |
| 314 |
|
which is not followed by a <code>--</code> or |
| 315 |
|
<code>!DOCTYPE</code>. The document is non-conforming.</p> |
| 316 |
|
|
| 317 |
|
<dl class="switch"> |
| 318 |
|
<dt>Comments</dt> |
| 319 |
|
<dd>In HTML document, comments must be introduced by |
| 320 |
|
<code class="example"><!--</code> (<code><!</code> |
| 321 |
|
<em>immediately</em> followed |
| 322 |
|
by <em>two</em> <code>-</code>s) and must be terminated by |
| 323 |
|
<code class="example">--></code>. |
| 324 |
|
Strings <code><!</code> not followed |
| 325 |
|
by <code>--</code> and <code><!-</code> not followed by |
| 326 |
|
<code>-</code> are not valid open delimiters for comments.</dd> |
| 327 |
|
<dt>Marked sections, including <code>CDATA</code> sections</dt> |
| 328 |
|
<dd>Marked sections are not allowed in HTML document.</dd> |
| 329 |
|
<dt>Markup declarations</dt> |
| 330 |
|
<dd>Markup declarations, except for <code>DOCTYPE</code> |
| 331 |
|
and comment declarations, are not allowed in HTML document.</dd> |
| 332 |
|
<dt>String <code><!</code></dt> |
| 333 |
|
<dd>String <code><!</code> must be escaped as |
| 334 |
|
<code class="example">&lt;!</code>.</dd> |
| 335 |
|
</dl> |
| 336 |
|
</d:desc> |
| 337 |
|
</d:item> |
| 338 |
|
|
| 339 |
|
<d:item name="bogus end tag" |
| 340 |
|
class="tokenize-error"> |
| 341 |
|
<d:message xml:lang="en">String <code></</code> is not followed |
| 342 |
|
by tag name.</d:message><!-- </ non-name-start-char-non-EOF --> |
| 343 |
|
<d:desc xml:lang="en"> |
| 344 |
|
<p>There is a <code><</code> (<code>U+003C</code> |
| 345 |
|
<code class="charname">LESS-THAN SIGN</code>) character |
| 346 |
|
immediately followed by a <code>/</code> (<code>U+005F</code> |
| 347 |
|
<code>SOLIDUS</code>) character, which is not part |
| 348 |
|
of any end tag, in the input stream. The document |
| 349 |
|
is non-conforming.</p> |
| 350 |
|
|
| 351 |
|
<p>The <code></</code> sequence not followed by a |
| 352 |
|
tag name is parsed as an opening of bogus comment.</p> |
| 353 |
|
|
| 354 |
|
<p>The <code></</code> sequence as string data must |
| 355 |
|
be escaped as: |
| 356 |
|
<pre class="html example"><code>&lt;/</code></pre> |
| 357 |
|
</p> |
| 358 |
|
</d:desc> |
| 359 |
|
</d:item> |
| 360 |
|
|
| 361 |
<d:item name="dash in comment" |
<d:item name="dash in comment" |
| 362 |
class="tokenize-error"> |
class="tokenize-error"> |
| 363 |
<d:message xml:lang="en">There is a <code>--</code> sequence |
<d:message xml:lang="en">There is a <code>--</code> sequence |
| 390 |
|
|
| 391 |
<d:item name="nestc" |
<d:item name="nestc" |
| 392 |
class="tokenize-error"> |
class="tokenize-error"> |
| 393 |
<d:message xml:lang="en">Void element syntax (<code>/></code>) cannot be |
<d:message xml:lang="en">Polytheistic slash (<code>/></code>) cannot be |
| 394 |
used for this element.</d:message> |
used for this element.</d:message> |
| 395 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 396 |
<p>Void element syntax (<code>/></code>) must not be used |
<p>Polytheistic slash (<code>/></code>) must not be used |
| 397 |
for the element. The document is non-conforming.</p> |
for the element. The document is non-conforming.</p> |
| 398 |
|
|
| 399 |
<p>The void element syntax can only be |
<p>The polytheistic slash can only be |
| 400 |
used for <code>base</code>, <code>link</code>, <code>meta</code>, |
used for <code>base</code>, <code>link</code>, <code>meta</code>, |
| 401 |
<code>hr</code>, <code>br</code>, <code>img</code>, |
<code>hr</code>, <code>br</code>, <code>img</code>, |
| 402 |
<code>embed</code>, <code>param</code>, <code>area</code>, |
<code>embed</code>, <code>param</code>, <code>area</code>, |
| 403 |
<code>col</code>, and <code>input</code> elements.</p> |
<code>col</code>, and <code>input</code> elements.</p> |
| 404 |
|
|
| 405 |
<p>Note that, unlike in XML, the void element syntax has |
<dl class="switch"> |
| 406 |
|
<dt><code><script/></code></dt> |
| 407 |
|
<dd><p>The polytheistic slash cannot be used for <code>script</code> |
| 408 |
|
element. Even for an empty <code>script</code> element, |
| 409 |
|
there must be an explicit end tag |
| 410 |
|
<code class="html example"></script></code>.</p> |
| 411 |
|
|
| 412 |
|
<p><strong>NOTE</strong>: Though some user agents interpret |
| 413 |
|
polytheistic slash for <code>script</code> element as the |
| 414 |
|
closing of the element, such usage is not allowed under |
| 415 |
|
the current standard.</p></dd> |
| 416 |
|
<dt><code><basefont/></code>, <code><bgsound/></code>, |
| 417 |
|
<code><frame/></code>, <code><keygen/></code>, |
| 418 |
|
<code><spacer/></code>, <code><wbr/></code></dt> |
| 419 |
|
<dd>These elements are themselves non-conforming.</dd> |
| 420 |
|
<!-- isindex, image --> |
| 421 |
|
<dt><code><command/></code>, <code><event-source/></code>, |
| 422 |
|
<code><nest/></code>, or <code><source/></code></dt> |
| 423 |
|
<dd>Future revision of HTML5 parsing algorithm is expected |
| 424 |
|
to allow polytheistic slash for these elements.</dd> |
| 425 |
|
<dt><code><a/></code>, <code><p/></code></dt> |
| 426 |
|
<dd>These elements are not always empty and therefore |
| 427 |
|
polytheistic slash is not allowed. Use explicit end tag |
| 428 |
|
to represent empty element as: |
| 429 |
|
<pre class="example html"><code><p></p></code></pre> |
| 430 |
|
</dd> |
| 431 |
|
</dl> |
| 432 |
|
|
| 433 |
|
<p>Note that, unlike in XML, the polytheistic slash has |
| 434 |
no effect in HTML.</p> |
no effect in HTML.</p> |
| 435 |
</d:desc> |
</d:desc> |
| 436 |
</d:item> |
</d:item> |
| 439 |
<d:item name="pio" |
<d:item name="pio" |
| 440 |
class="tokenize-error"> |
class="tokenize-error"> |
| 441 |
<d:message xml:lang="en">Processing instruction |
<d:message xml:lang="en">Processing instruction |
| 442 |
(<code><?<var>...</var>?></code>) cannot be used.</d:message> |
(<code><?<var>...</var>></code>) cannot be used.</d:message> |
| 443 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 444 |
<p>Processing instructions (<code><?<var>...</var>?></code>), |
<p>Processing instructions (<code><?<var>...</var>?></code>), |
| 445 |
including XML declaration (<code><?xml <var>...</var>?></code>) |
including XML declaration (<code><?xml <var>...</var>?></code>) |
| 446 |
and XML style sheet <abbr title="processing instruction">PI</abbr> |
and XML style sheet <abbr title="processing instruction">PI</abbr> |
| 447 |
(<code><xml-stylesheet <var>...</var>?></code>), are not allowed |
(<code><?xml-stylesheet <var>...</var>?></code>), are not allowed |
| 448 |
in the HTML syntax. The document is non-conforming.</p> |
in the HTML syntax. The document is non-conforming.</p> |
| 449 |
|
|
| 450 |
<p>If it is necessary to embed a processing instruction |
<dl class="switch"> |
| 451 |
in the HTML document, you must use the XML syntax instead.</p> |
<dt><code><?xbl?></code> (<abbr>XBL</abbr> Association)</dt> |
| 452 |
|
<dd>An <abbr>XBL</abbr> binding cannot be associated by |
| 453 |
<p>In the HTML syntax, XML declaration is not necessary.</p> |
<abbr title="processing instruction">PI</abbr> in <abbr>HTML</abbr> |
| 454 |
|
document. Use <code>binding</code> property in <abbr>CSS</abbr> |
| 455 |
<p>Instead of XML style sheet, |
style sheet as: |
| 456 |
<abbr title="processing instruction">PI</abbr>s, you must |
<pre class="html example"><code><style> |
| 457 |
use the HTML <code>link</code> element whose <code>rel</code> |
p { |
| 458 |
attribute is set to <code>stylesheet</code> (or |
binding: url(binding.xbl); |
| 459 |
<code>alternate stylesheet</code> for an aleternate style sheet).</p> |
} |
| 460 |
|
</style></code></pre> |
| 461 |
|
</dd> |
| 462 |
|
<dt><code><?xml?></code> (XML declaration)</dt> |
| 463 |
|
<dd>XML declaration is unnecessary for HTML documents.</dd> |
| 464 |
|
<dt><code><?xml-stylesheet?></code> (XML style sheet |
| 465 |
|
<abbr title="processing instruction">PI</abbr>)</dt> |
| 466 |
|
<dd>Use HTML <code>link</code> element with <code>rel</code> |
| 467 |
|
attribute set to <code>stylesheet</code> (or, |
| 468 |
|
<code>alternate stylesheet</code> for an alternate style |
| 469 |
|
sheet). |
| 470 |
|
<pre class="example html"><code><link rel=stylesheet href="path/to/stylesheet.css"></code></pre> |
| 471 |
|
</dd> |
| 472 |
|
<dt><code><?php?></code> or |
| 473 |
|
<code><? <var>... <abbr>PHP</abbr> code ...</var> ?></code> |
| 474 |
|
(<abbr>PHP</abbr> code)</dt> |
| 475 |
|
<dd>The conformance checker does <em>not</em> support |
| 476 |
|
checking for PHP source documents.</dd> |
| 477 |
|
<dt>Other processing instructions</dt> |
| 478 |
|
<dd>Processing instructions cannot be inserted in an HTML |
| 479 |
|
document. Use XML document or insert |
| 480 |
|
<code>ProcessingInstruction</code> node by scripting.</dd> |
| 481 |
|
</dl> |
| 482 |
|
|
| 483 |
<p>Web browsers will parse processing instructions as bogus |
<p>Web browsers will parse processing instructions as bogus |
| 484 |
comments. Some legacy Web browsers, such as IE:mac and |
comments. Some legacy Web browsers, such as IE:mac and |
| 485 |
some mobile browsers, will display processing instructions |
some mobile Web browsers, will display processing instructions |
| 486 |
as string.</p> |
as string.</p> |
| 487 |
</d:desc> |
</d:desc> |
| 488 |
</d:item> |
</d:item> |
| 532 |
<d:item name="in body" |
<d:item name="in body" |
| 533 |
class="parse-error"> |
class="parse-error"> |
| 534 |
<d:message xml:lang="en">Tag <code><<var>$0</var>></code> |
<d:message xml:lang="en">Tag <code><<var>$0</var>></code> |
| 535 |
is not allowed in a <code>body</code> element.</d:message> |
is not allowed in the <code>body</code> element.</d:message> |
| 536 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 537 |
<p>The start or end tag of an element, which |
<p>The start or end tag of an element, which |
| 538 |
cannot be a descendant of <code>body</code> element, appears |
cannot be a descendant of <code>body</code> element, appears |
| 543 |
|
|
| 544 |
<d:item name="in head:head" |
<d:item name="in head:head" |
| 545 |
class="parse-error"> |
class="parse-error"> |
| 546 |
<d:message xml:lang="en">Start tag <code><<var>head</var>></code> |
<d:message xml:lang="en">Start tag <code><head></code> |
| 547 |
is not allowed in the <code>head</code> element.</d:message> |
is not allowed in the <code>head</code> element.</d:message> |
| 548 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 549 |
<p>There is a start tag <code><head></code> in the |
<p>There is a start tag <code><head></code> in the |
| 618 |
</p> |
</p> |
| 619 |
|
|
| 620 |
<p>Only white space characters and comments are allowed |
<p>Only white space characters and comments are allowed |
| 621 |
before the <code>DOCTYPE</code>.</p> |
before the <code>DOCTYPE</code>. XML declaration is <em>not</em> |
| 622 |
|
allowed in HTML document.</p> |
| 623 |
</d:desc> |
</d:desc> |
| 624 |
</d:item> |
</d:item> |
| 625 |
|
|
| 631 |
<p>End tag of an element is not found before, for example, |
<p>End tag of an element is not found before, for example, |
| 632 |
an end tag of another element appears or |
an end tag of another element appears or |
| 633 |
the end of the document. The document is non-conforming.</p> |
the end of the document. The document is non-conforming.</p> |
| 634 |
|
|
| 635 |
|
<p>Only <code>body</code>, <code>colgroup</code>, <code>dd</code>, |
| 636 |
|
<code>dt</code>, <code>head</code>, <code>html</code>, <code>li</code>, |
| 637 |
|
<code>ol</code>, <code>option</code>, <code>optgroup</code>, |
| 638 |
|
<code>p</code>, <code>rb</code>, <code>rp</code>, <code>rt</code>, |
| 639 |
|
<code>tbody</code>, <code>td</code>, <code>tfoot</code>, |
| 640 |
|
<code>th</code>, <code>thead</code>, <code>tr</code>, |
| 641 |
|
<code>ul</code> end tag can be omitted in HTML documents. |
| 642 |
|
For any element except for void element, there must be an explicit |
| 643 |
|
end tag.</p> |
| 644 |
|
|
| 645 |
|
<dl class="switch"> |
| 646 |
|
<dt>HTML <code>canvas</code> element</dt> |
| 647 |
|
<dd>Though the element is void in earlier versions of Safari, |
| 648 |
|
the <code>canvas</code> element is <em>no</em> longer |
| 649 |
|
defined as empty. There must be an end tag |
| 650 |
|
<code class="html example"></canvas></code>.</dd> |
| 651 |
|
</dl> |
| 652 |
|
|
| 653 |
|
<p>Note that misnesting tags, such as |
| 654 |
|
<code class="bad example"><a><b></a></b></code>, are not |
| 655 |
|
allowed and they also cause this error.</p> |
| 656 |
</d:desc> |
</d:desc> |
| 657 |
</d:item> |
</d:item> |
| 658 |
|
|
| 681 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 682 |
<p>The document contains a <code>DOCTYPE</code> declaration |
<p>The document contains a <code>DOCTYPE</code> declaration |
| 683 |
that is different from HTML5 <code>DOCTYPE</code> (i.e. |
that is different from HTML5 <code>DOCTYPE</code> (i.e. |
| 684 |
<code><!DOCTYPE HTML></code>). The document is non-conforming.</p> |
<code class="example html"><!DOCTYPE HTML></code>). |
| 685 |
|
The document is non‐conforming.</p> |
| 686 |
|
|
| 687 |
<p>The document might or might not be conformant to |
<p>The document might or might not be conformant to |
| 688 |
some version of HTML. However, conformance to any HTML |
some version of HTML. However, conformance to any HTML |
| 702 |
|
|
| 703 |
<p>For any end tag in HTML document, there must be a |
<p>For any end tag in HTML document, there must be a |
| 704 |
corresponding start tag.</p> |
corresponding start tag.</p> |
| 705 |
|
|
| 706 |
|
<dl class="switch"> |
| 707 |
|
<dt>HTML <code>base</code>, <code>basefont</code>, |
| 708 |
|
<code>bgsound</code>, <code>br</code>, <code>col</code>, |
| 709 |
|
<code>embed</code>, <code>frame</code>, <code>hr</code>, |
| 710 |
|
<code>image</code>, <code>img</code>, <code>input</code>, |
| 711 |
|
<code>isindex</code>, <code>link</code>, <code>meta</code>, |
| 712 |
|
<code>param</code>, <code>spacer</code>, or <code>wbr</code> element</dt> |
| 713 |
|
<dd>End tag is not allowed for these elements, since |
| 714 |
|
those content must always be empty. Remove end tag.</dd> |
| 715 |
|
<!-- keygen --> |
| 716 |
|
<!-- command, event-source, nest, source --> |
| 717 |
|
</dl> |
| 718 |
</d:desc> |
</d:desc> |
| 719 |
</d:item> |
</d:item> |
| 720 |
|
|
| 759 |
must contain a <code><var>$0</var></code> child element. |
must contain a <code><var>$0</var></code> child element. |
| 760 |
The document is non-conforming.</p> |
The document is non-conforming.</p> |
| 761 |
|
|
| 762 |
<p>For example: |
<dl class="switch"> |
| 763 |
<ul> |
<dt>HTML <code>head</code> element</dt> |
| 764 |
<li>The <code>head</code> element must contain exactly one |
<dd>There must be a <code>title</code> child element.</dd> |
| 765 |
<code>title</code> child element.</li> |
<dt>HTML <code>html</code> element</dt> |
| 766 |
<li><a href="#child-element-missing:td%7Cth">The <code>tr</code> |
<dd>There must be a <code>head</code> child element followed |
| 767 |
element must contain one or more <code>td</code> or <code>th</code> |
by a <code>body</code> element.</dd> |
| 768 |
child element.</a></li> |
<dt>HTML <code>tr</code> element</dt> |
| 769 |
</ul> |
<dd><a href="#child-element-missing:td%7Cth">There must be |
| 770 |
</p> |
one or more <code>td</code> or <code>th</code> child element.</a></dd> |
| 771 |
|
</dl> |
| 772 |
</d:desc> |
</d:desc> |
| 773 |
</d:item> |
</d:item> |
| 774 |
|
|
| 791 |
<p>An element appears where it is not allowed. The document |
<p>An element appears where it is not allowed. The document |
| 792 |
is non-conforming.</p> |
is non-conforming.</p> |
| 793 |
|
|
|
<p><strong>Note</strong>: The conformance checker does |
|
|
<em>not</em> support form elements yet.</p> |
|
|
|
|
| 794 |
<p>Possible causes: |
<p>Possible causes: |
| 795 |
<dl class="switch"> |
<dl class="switch"> |
| 796 |
<dt>If the element with the error is an inline-level element, |
<dt>If the element with the error is an inline-level element, |
| 801 |
|
|
| 802 |
<p>Any inline-level content must be put |
<p>Any inline-level content must be put |
| 803 |
in e.g. paragraph element such as <code>p</code>.</p></dd> |
in e.g. paragraph element such as <code>p</code>.</p></dd> |
| 804 |
<dt>If the element with the error is a block-level element, |
<dt>If it is a block-level elements, such as <code>aside</code>, |
| 805 |
such as <code>div</code>, <code>h<var>n</var></code>, or |
<code>div</code>, <code>h<var>n</var></code>, |
| 806 |
<code>section</code></dt> |
<code>p</code>, or <code>section</code></dt> |
| 807 |
<dd><p>Though some elements such as <code>div</code>, |
<dd><dl class="switch"> |
| 808 |
<code>li</code>, and <code>td</code> allow |
<dt>If the parent element is <code>div</code>, |
| 809 |
<em>either one</em> of block-level or inline-level content |
<code>li</code>, <code>td</code>, or <code>th</code></dt> |
| 810 |
is allowed. If there is a block-level content, |
<!-- @@ TODO: more... --> |
| 811 |
any inline-level content must be put |
<!-- @@ TODO: <p><ul><li><p> --> |
| 812 |
in e.g. paragraph element such as <code>p</code>.</p></dd> |
<dd><p>The parent element allows <em>either</em> |
| 813 |
|
block-level or inline-level content. If there is a |
| 814 |
|
block-level content, any inline-level content must be |
| 815 |
|
put in e.g. paragraph element such as <code>p</code>.</p> |
| 816 |
|
<p>For example, an HTML document fragment |
| 817 |
|
<code class="html bad example"><div><p>Hello!</p> World!</div></code> |
| 818 |
|
is non-conforming, since a word <q>World!</q> does not belong |
| 819 |
|
to any paragraph. (If not part of any paragraph, what is |
| 820 |
|
it!?) A conforming example would be: |
| 821 |
|
<pre class="html example"><code><div><p>Hello!</p> <p>World!</p></div></code></pre> |
| 822 |
|
</p></dd> |
| 823 |
|
<dt>If the parent element does <em>not</em> allow |
| 824 |
|
block-level elements as content</dt> |
| 825 |
|
<dd>The element is not allowed to be inserted here. |
| 826 |
|
For example, a <code>div</code> element cannot be |
| 827 |
|
a child of an <code>h1</code> element.</dd> |
| 828 |
|
</dl></dd> |
| 829 |
<dt>If the element with the error is a <code>noscript</code> element</dt> |
<dt>If the element with the error is a <code>noscript</code> element</dt> |
| 830 |
<dd>The <code>noscript</code> element is allowed only in the context |
<dd>The <code>noscript</code> element is allowed only in the context |
| 831 |
where a block-level or inline-level content is expected |
where a block-level or inline-level content is expected |
| 832 |
and in the <code>head</code> element. |
and in the <code>head</code> element. |
| 833 |
It cannot be used in e.g. <code>ul</code>, <code>table</code>, |
It cannot be used in e.g. <code>ul</code>, <code>table</code>, |
| 834 |
or <code>select</code>.</dd> |
or <code>select</code>.</dd> |
| 835 |
<dt>If the element with the error is the <code>html</code> element |
<dt>If the element with the error is <code>blink</code>, |
| 836 |
that is the root element of an XHTML document</dt> |
<code>center</code>, or <code>marquee</code> element</dt> |
| 837 |
<dd><p>In an XHTML document, the root <code>html</code> |
<dd>These elements are not part of the HTML standard. |
| 838 |
element must have an <code>xmlns</code> attribute |
Use CSS for styling control.</dd> |
| 839 |
whose value is set to |
|
| 840 |
<code>http://www.w3.org/1999/xhtml</code>.</p></dd> |
<dt><code>button</code>, <code>datalist</code>, |
| 841 |
|
<code>fieldset</code>, <code>form</code>, |
| 842 |
|
<code>input</code>, <code>label</code>, |
| 843 |
|
<code>optgroup</code>, <code>option</code>, <code>output</code>, |
| 844 |
|
<code>rb</code>, <code>rp</code>, <code>rt</code>, <code>ruby</code>, |
| 845 |
|
<code>textarea</code>, or <code>textarea</code> element</dt> |
| 846 |
|
<!-- rbc, rtc ? --> |
| 847 |
|
<dd>These elements are intentionally not supported by the conformance |
| 848 |
|
checker <em>yet</em>.</dd> |
| 849 |
</dl> |
</dl> |
| 850 |
</p> |
</p> |
| 851 |
</d:desc> |
</d:desc> |
| 852 |
</d:item> |
</d:item> |
| 853 |
|
|
| 854 |
|
<d:item name="element not allowed:root" |
| 855 |
|
class="content-model-error"> |
| 856 |
|
<d:message xml:lang="en">This element is not allowed as a root |
| 857 |
|
element.</d:message> |
| 858 |
|
<d:desc xml:lang="en"> |
| 859 |
|
<p>An element that is not allowed as the root element |
| 860 |
|
is used as the root element of the document. The document is |
| 861 |
|
non-conforming, as far as the conformance checker can tell.</p> |
| 862 |
|
|
| 863 |
|
<dl class="switch"> |
| 864 |
|
<dt><code>html</code> element in an XHTML document</dt> |
| 865 |
|
<dd><p>In <abbr>XHTML</abbr> document, the root <code>html</code> |
| 866 |
|
element must have an <code>xmlns</code> attribute as: |
| 867 |
|
<pre class="xml example"><code><html xmlns="http://www.w3.org/1999/xhtml"></code></pre></p></dd> |
| 868 |
|
<dt><code>rss</code> element</dt> |
| 869 |
|
<dd><p>The document is written in some version of RSS.</p> |
| 870 |
|
<p>The conformance checker does not support any version |
| 871 |
|
of RSS. Use Atom 1.0 for feed documents.</p></dd> |
| 872 |
|
<dt><code>feed</code> element</dt> |
| 873 |
|
<dd><p>The Atom <code>feed</code> element must be |
| 874 |
|
in the <code>http://www.w3.org/2005/Atom</code> |
| 875 |
|
namespace as: |
| 876 |
|
<pre class="xml example"><code><feed xmlns="http://www.w3.org/2005/Atom"></code></pre> |
| 877 |
|
</p> |
| 878 |
|
<p>The conformance checker does not support Atom 0.3. |
| 879 |
|
Use Atom 1.0 for feed documents.</p></dd> |
| 880 |
|
</dl> |
| 881 |
|
</d:desc> |
| 882 |
|
</d:item> |
| 883 |
|
|
| 884 |
<d:item name="ps element missing" |
<d:item name="ps element missing" |
| 885 |
class="content-model-error"> |
class="content-model-error"> |
| 886 |
<d:message xml:lang="en">There is no <code><var>$0</var></code> |
<d:message xml:lang="en">There is no <code><var>$0</var></code> |
| 908 |
is non-conforming.</p> |
is non-conforming.</p> |
| 909 |
|
|
| 910 |
<p>Some attribute is defined as <i>required</i>. |
<p>Some attribute is defined as <i>required</i>. |
|
For example, any <code>img</code> element must have |
|
|
<code>alt</code> and <code>src</code> attributes specified. |
|
| 911 |
Without required attributes specified, user agents |
Without required attributes specified, user agents |
| 912 |
cannot provide the full functionality of the element |
cannot provide full functionality of the element to the user.</p> |
| 913 |
to the user.</p> |
|
| 914 |
|
<dl class="switch"> |
| 915 |
|
<dt>HTML <code>img</code> element</dt> |
| 916 |
|
<dd>The <code>src</code> attribute must be specified. |
| 917 |
|
Additionally, the <code>alt</code> attribute must be specified |
| 918 |
|
in many cases.</dd> |
| 919 |
|
<dt>HTML <code>link</code> element</dt> |
| 920 |
|
<dd>The <code>rel</code> attribute must be specified. |
| 921 |
|
Note that the <code>rev</code> attribute is obsolete.</dd> |
| 922 |
|
</dl> |
| 923 |
|
</d:desc> |
| 924 |
|
</d:item> |
| 925 |
|
|
| 926 |
|
<d:item name="attribute not allowed" class="attribute-error"> |
| 927 |
|
<d:message xml:lang="en">Attribute |
| 928 |
|
<code><var>{local-name}</var></code> is not allowed for |
| 929 |
|
<code><var>{element-local-name}</var></code> element.</d:message> |
| 930 |
|
<d:desc xml:lang="en"> |
| 931 |
|
<p>An attribute is specified where it is not allowed. |
| 932 |
|
The document is non-conforming.</p> |
| 933 |
|
|
| 934 |
|
<dl> |
| 935 |
|
<dt>HTML <code>meta</code> element</dt> |
| 936 |
|
<dd>For HTML <code>meta</code> element, <em>only one</em> of |
| 937 |
|
<code>name</code>, <code>http-equiv</code>, or <code>charset</code> |
| 938 |
|
attribute is allowed.</dd> |
| 939 |
|
</dl> |
| 940 |
</d:desc> |
</d:desc> |
| 941 |
</d:item> |
</d:item> |
| 942 |
|
|
| 944 |
class="attribute-error"> |
class="attribute-error"> |
| 945 |
<d:message xml:lang="en">The <code>xml:lang</code> attribute is not |
<d:message xml:lang="en">The <code>xml:lang</code> attribute is not |
| 946 |
allowed in HTML document.</d:message> |
allowed in HTML document.</d:message> |
| 947 |
<d:desc> |
<d:desc xml:lang="en"> |
| 948 |
<p>The <code>xml:lang</code> attribute is not allowed in |
<p>The <code>xml:lang</code> attribute is not allowed in |
| 949 |
HTML document. The document is non-conforming.</p> |
HTML document. The document is non-conforming.</p> |
| 950 |
|
|
| 951 |
<p>The <code>lang</code> attribute in the <code>null</code> |
<p>Use of the <code>xml:lang</code> attribute is conforming |
| 952 |
namespace for HTML elements is defined as conforming <em>only</em> for |
<em>only</em> in XML documents.</p> |
|
XML document.</p> |
|
| 953 |
|
|
| 954 |
<p>To specify natural language information in HTML document, |
<p>To specify natural language information in HTML document, |
| 955 |
use <code>lang</code> attribute instead.</p> |
use <code>lang</code> attribute instead.</p> |
| 990 |
XML document. The document is non-conforming.</p> |
XML document. The document is non-conforming.</p> |
| 991 |
|
|
| 992 |
<p>The <code>lang</code> attribute in <code>null</code> |
<p>The <code>lang</code> attribute in <code>null</code> |
| 993 |
namespace for HTML elements is defined as conforming <em>only</em> for |
namespace for HTML elements is conforming <em>only</em> in |
| 994 |
HTML document.</p> |
HTML documents.</p> |
| 995 |
|
|
| 996 |
<p>To specify natural language information in XML document, |
<p>To specify natural language information in XML document, |
| 997 |
use <code>xml:lang</code> attribute instead.</p> |
use <code>xml:lang</code> attribute instead.</p> |
| 1007 |
<p>The <code>xmlns</code> attribute in the <code>null</code> |
<p>The <code>xmlns</code> attribute in the <code>null</code> |
| 1008 |
namespace is not allowed in XHTML document.</p> |
namespace is not allowed in XHTML document.</p> |
| 1009 |
|
|
| 1010 |
<p>This error should not occur in conformance-checking |
<p>This error should not occur in conformance-checking of |
| 1011 |
static documents.</p> |
static documents.</p> |
| 1012 |
</d:desc> |
</d:desc> |
| 1013 |
</d:item> |
</d:item> |
| 1017 |
<section id="attribute-value-errors"> |
<section id="attribute-value-errors"> |
| 1018 |
<h2>Attribute Value Errors</h2> |
<h2>Attribute Value Errors</h2> |
| 1019 |
|
|
| 1020 |
|
<d:item name="charset:not registered" class="attribute-value-warning warning" |
| 1021 |
|
level="w"> |
| 1022 |
|
<d:message xml:lang="en">Character encoding name <code><var>$0</var></code> |
| 1023 |
|
is not registered.</d:message> |
| 1024 |
|
<d:desc xml:lang="en"> |
| 1025 |
|
<p>The specified character encoding name is not registered to |
| 1026 |
|
<abbr>IANA</abbr>. Use of registered character encoding name |
| 1027 |
|
is a good practice to facilitate interoperability.</p> |
| 1028 |
|
|
| 1029 |
|
<dl class="switch"> |
| 1030 |
|
<dt><code>EUC-TW</code></dt> |
| 1031 |
|
<dd><code>EUC-TW</code> is not registered. Unfortunately, there |
| 1032 |
|
is no registered name for that character encoding. Use |
| 1033 |
|
Big5 encoding with character encoding name <code>Big5</code> |
| 1034 |
|
if it is enough to represent the document.</dd> |
| 1035 |
|
<dt><code>ISO-2022-JP-1</code></dt> |
| 1036 |
|
<dd><code>ISO-2022-JP-1</code> is not registered, nevertheless |
| 1037 |
|
this character encoding name is documented in |
| 1038 |
|
<a href="urn:ietf:rfc:2237"><abbr>RFC</abbr> 2237</a>. Use |
| 1039 |
|
<code>ISO-2022-JP-2</code> instead, since that character encoding |
| 1040 |
|
is a superset of ISO-2022-JP-1.</dd> |
| 1041 |
|
<dt><code>ISO-2022-JP-3</code>, <code>ISO-2022-JP-3-plane1</code></dt> |
| 1042 |
|
<dd>These names are not registered and obsoleted in favor of |
| 1043 |
|
<code>ISO-2022-JP-2004</code> and |
| 1044 |
|
<code>ISO-2022-JP-2004-plane1</code>.</dd> |
| 1045 |
|
<dt><code>ISO-2022-JP-2003</code>, |
| 1046 |
|
<code>ISO-2022-JP-2003-plane1</code></dt> |
| 1047 |
|
<dd>These names are not registered and corrected to |
| 1048 |
|
<code>ISO-2022-JP-2004</code> and |
| 1049 |
|
<code>ISO-2022-JP-2004-plane1</code>.</dd> |
| 1050 |
|
<dt><code>ISO-2022-JP-2004</code>, |
| 1051 |
|
<code>ISO-2022-JP-2004-plane1</code></dt> |
| 1052 |
|
<dd>These names are not registered. Unfortunately, there is |
| 1053 |
|
no registered name for these character encodings.</dd> |
| 1054 |
|
<dt><code>UTF-8N</code></dt> |
| 1055 |
|
<dd><code>UTF-8N</code> is not registered. Character encoding |
| 1056 |
|
name <code>UTF-8</code> represents UTF-8 encoding with or |
| 1057 |
|
without <abbr>BOM</abbr>.</dd> |
| 1058 |
|
</dl> |
| 1059 |
|
|
| 1060 |
|
<p><strong>WARNING</strong>: This error might be raised for |
| 1061 |
|
a registered character encoding name, since the character encoding |
| 1062 |
|
name database of the conformance checker is not complete yet.</p> |
| 1063 |
|
</d:desc> |
| 1064 |
|
</d:item> |
| 1065 |
|
|
| 1066 |
|
<d:item name="charset:private" class="attribute-value-warning warning" |
| 1067 |
|
level="w"> |
| 1068 |
|
<d:message xml:lang="en"><code><var>$0</var></code> is a private |
| 1069 |
|
character encoding name.</d:message> |
| 1070 |
|
<d:desc xml:lang="en"> |
| 1071 |
|
<p>The specified character encoding name is a private name and |
| 1072 |
|
not registered to <abbr>IANA</abbr>. Use of registered character |
| 1073 |
|
encoding name is a good practice to facilitate interoperability.</p> |
| 1074 |
|
|
| 1075 |
|
<dl class="switch"> |
| 1076 |
|
<dt><code>x-euc-jp</code></dt> |
| 1077 |
|
<dd>Use <code>EUC-JP</code> for the Japanese <abbr>EUC</abbr> |
| 1078 |
|
character encoding.</dd> |
| 1079 |
|
<dt><code>x-sjis</code></dt> |
| 1080 |
|
<dd>Use <code>Shift_JIS</code> for standard Shift encoding scheme of |
| 1081 |
|
<abbr>JIS</abbr> coded character set, or <code>Windows-31J</code> |
| 1082 |
|
for Microsoft standard character set as implemented by |
| 1083 |
|
Microsoft Windows.</dd> |
| 1084 |
|
</dl> |
| 1085 |
|
</d:desc> |
| 1086 |
|
</d:item> |
| 1087 |
|
|
| 1088 |
|
<d:item name="charset:syntax error" class="attribute-value-error" |
| 1089 |
|
level="m"> |
| 1090 |
|
<d:message xml:lang="en">The specified value is syntactically not a |
| 1091 |
|
character encoding name.</d:message> |
| 1092 |
|
<d:desc xml:lang="en"> |
| 1093 |
|
<p>The attribute value must be a character encoding name. However, |
| 1094 |
|
the specified value is not a character encoding name syntactically. |
| 1095 |
|
The document is non‐conforming.</p> |
| 1096 |
|
<p>Character encoding name is a string of <abbr>ASCII</abbr> |
| 1097 |
|
printable characters, up to 40 characters.</p> |
| 1098 |
|
</d:desc> |
| 1099 |
|
</d:item> |
| 1100 |
|
|
| 1101 |
<d:item name="enumerated:invalid" |
<d:item name="enumerated:invalid" |
| 1102 |
class="attribute-value-error"> |
class="attribute-value-error"> |
| 1103 |
<d:message xml:lang="en">This attribute only allow a limited set of |
<d:message xml:lang="en">This attribute only allow a limited set of |
| 1104 |
values and the specified value <code><var>{@}</var></code> is not one |
values and the specified value <code><var>{@}</var></code> is not one |
| 1105 |
of them.</d:message> |
of them.</d:message> |
| 1106 |
|
<d:desc xml:lang="en"> |
| 1107 |
|
<p>For this attribute only several values are allowed and the |
| 1108 |
|
value of the attribute is not one of them. The document |
| 1109 |
|
is non-conforming.</p> |
| 1110 |
|
|
| 1111 |
|
<dl> |
| 1112 |
|
<dt>HTML <code>meta</code> element, <code>http-equiv</code> attribute</dt> |
| 1113 |
|
<dd><p>Only values <code>Default-Style</code> and <code>Refresh</code> |
| 1114 |
|
are allowed.</p> |
| 1115 |
|
<p>Value <code>Content-Type</code> is obsolete; for charset |
| 1116 |
|
declaration, the <code>charset</code> attribute can be used as: |
| 1117 |
|
<pre class="html example"><code><meta charset="<var>charset-name</var>"></code></pre> |
| 1118 |
|
... where <var>charset-name</var> is a name of the character encoding |
| 1119 |
|
of the document, such as <code>utf-8</code>.</p> |
| 1120 |
|
<p>Values <code>Content-Style-Type</code> and |
| 1121 |
|
<code>Content-Script-Type</code> are currently not allowed.</p> |
| 1122 |
|
<p>Value <code>Keywords</code> is not allowed. Use |
| 1123 |
|
<code>name</code> attribute instead of <code>http-equiv</code> |
| 1124 |
|
attribute.</p> |
| 1125 |
|
<p>Values <code>Expires</code>, <code>Pragma</code>, |
| 1126 |
|
and <code>Cache-Control</code> are not allowed; |
| 1127 |
|
use <em>real</em> HTTP header fields for cache control.</p></dd> |
| 1128 |
|
</dl> |
| 1129 |
|
</d:desc> |
| 1130 |
|
</d:item> |
| 1131 |
|
|
| 1132 |
|
<d:item name="enumerated:invalid:http-equiv:content-type" |
| 1133 |
|
class="attribute-value-error"> |
| 1134 |
|
<d:message xml:lang="en">Character encoding declaration syntax |
| 1135 |
|
<code class="html bad example"><meta http-equiv="Content-Type" content="text/html; charset=<var>charset-name</var>"></code> |
| 1136 |
|
is obsolete.</d:message> |
| 1137 |
|
<d:desc xml:lang="en"> |
| 1138 |
|
<p>Old long character encoding declaration syntax |
| 1139 |
|
<code class="html bad example"><meta http-equiv="Content-Type" content="text/html; charset=<var>charset-name</var>"></code> |
| 1140 |
|
is in use. The document is non‐conforming.</p> |
| 1141 |
|
|
| 1142 |
|
<p>The new character encoding declaration syntax is: |
| 1143 |
|
<pre class="html example"><code><meta charset="<var>charset-name</var>"></code></pre> |
| 1144 |
|
</p> |
| 1145 |
|
</d:desc> |
| 1146 |
</d:item> |
</d:item> |
| 1147 |
|
|
| 1148 |
<d:item name="duplicate ID" |
<d:item name="duplicate ID" |
| 1177 |
<p>The specified link type is non-conforming, and therefore |
<p>The specified link type is non-conforming, and therefore |
| 1178 |
the document is non-conforming.</p> |
the document is non-conforming.</p> |
| 1179 |
|
|
| 1180 |
<dl> |
<dl class="switch"> |
| 1181 |
<dt>Link type <code>contents</code></dt> |
<dt>Link type <code>contents</code></dt> |
| 1182 |
<dd>Use link type <code>index</code>.</dd> |
<dd>Use link type <code>index</code>.</dd> |
| 1183 |
<dt>Link type <code>copyright</code></dt> |
<dt>Link type <code>copyright</code></dt> |
| 1184 |
<dd>Use link type <code>license</code>.</dd> |
<dd>Use link type <code>license</code>.</dd> |
| 1185 |
<dt>Link type <code>home</code></dt> |
<dt>Link type <code>home</code></dt> |
| 1186 |
<dd>Use link type <code>index</code>.</dd> |
<dd>Use link type <code>index</code>.</dd> |
| 1187 |
|
<dt>Link type <code>previous</code></dt> |
| 1188 |
|
<dd>Use link type <code>prev</code>.</dd> |
| 1189 |
<dt>Link type <code>start</code></dt> |
<dt>Link type <code>start</code></dt> |
| 1190 |
<dd>Use link type <code>first</code>.</dd> |
<dd>Use link type <code>first</code>.</dd> |
| 1191 |
<dt>Link type <code>toc</code></dt> |
<dt>Link type <code>toc</code> or <code>top</code></dt> |
| 1192 |
<dd>Use link type <code>index</code>.</dd> |
<dd>Use link type <code>index</code>.</dd> |
| 1193 |
</dl> |
</dl> |
| 1194 |
</d:desc> |
</d:desc> |
| 1195 |
</d:item> |
</d:item> |
| 1196 |
|
|
| 1197 |
|
<d:item name="mismatched charset name" class="attribute-value-error" |
| 1198 |
|
level="m"> |
| 1199 |
|
<d:message xml:lang="en">Character encoding name <code><var>$1</var></code> |
| 1200 |
|
is different from document character encoding |
| 1201 |
|
<code><var>$0</var></code>.</d:message> |
| 1202 |
|
<d:desc xml:lang="en"> |
| 1203 |
|
<p>The specified character encoding name is different from |
| 1204 |
|
the character encoding of the document. The document |
| 1205 |
|
is non‐conforming.</p> |
| 1206 |
|
</d:desc> |
| 1207 |
|
</d:item> |
| 1208 |
|
|
| 1209 |
<d:item name="reserved browsing context name" |
<d:item name="reserved browsing context name" |
| 1210 |
class="attribute-value-error"> |
class="attribute-value-error"> |
| 1211 |
<d:message xml:lang="en">Browsing context name |
<d:message xml:lang="en">Browsing context name |
| 1243 |
|
|
| 1244 |
<p><strong>Warning</strong>: The data served to the |
<p><strong>Warning</strong>: The data served to the |
| 1245 |
conforming checker might be out of date; it might have already |
conforming checker might be out of date; it might have already |
| 1246 |
been accepted or rejected, depending on which the document |
been accepted or rejected. The document might or might not be |
| 1247 |
might be conforming or non-conforming. See WHATWG Wiki |
conforming depending on the status. See WHATWG Wiki |
| 1248 |
for the latest information.</p> |
for the latest information.</p> |
| 1249 |
</d:desc> |
</d:desc> |
| 1250 |
</d:item> |
</d:item> |
| 1279 |
The document is non-conforming.</p> |
The document is non-conforming.</p> |
| 1280 |
|
|
| 1281 |
<p>For example, the table below is non-conforming: |
<p>For example, the table below is non-conforming: |
| 1282 |
<pre class="html non-conforming example"><code><table> |
<pre class="html bad example"><code><table> |
| 1283 |
<tbody> |
<tbody> |
| 1284 |
<tr><td rowspan=2></td></tr> |
<tr><td rowspan=2></td></tr> |
| 1285 |
</tbody> |
</tbody> |
| 1286 |
</table></code></pre> |
</table></code></pre> |
| 1287 |
... is non-conforming, since the second row contains only |
... since the second row contains only |
| 1288 |
a cell that spans the first and the second rows.</p> |
a cell that spans between first and second rows.</p> |
| 1289 |
</d:desc> |
</d:desc> |
| 1290 |
</d:item> |
</d:item> |
| 1291 |
|
|
| 1298 |
class="should" level="s"> |
class="should" level="s"> |
| 1299 |
<d:message xml:lang="en"><code><var>{@}</var></code>: An <em>obsolete</em> |
<d:message xml:lang="en"><code><var>{@}</var></code>: An <em>obsolete</em> |
| 1300 |
subtype is used.</d:message> |
subtype is used.</d:message> |
| 1301 |
|
<d:item xml:lang="en"> |
| 1302 |
|
<p>The specified Internet Media Type is registered with status |
| 1303 |
|
of <i>OBSOLETE</i>.</p><!-- @@ SHOULD NOT? --> |
| 1304 |
|
|
| 1305 |
|
<dl class="swtich"> |
| 1306 |
|
<dt>Media type <code>text/ecmascript</code></dt> |
| 1307 |
|
<dd>Media type <code>text/ecmascript</code> is obsoleted in |
| 1308 |
|
favor of <code>application/ecmascript</code>. Note that |
| 1309 |
|
<code>text/javascript</code> would be better alternative |
| 1310 |
|
for many cases.</dd> |
| 1311 |
|
<dt>Media type <code>text/javascript</code></dt> |
| 1312 |
|
<dd>Media type <code>text/javascript</code> is obsoleted by |
| 1313 |
|
<abbr>IETF</abbr> with backward incompatible alternate |
| 1314 |
|
<code>application/javascript</code> for architectural |
| 1315 |
|
purity.<!-- @@ ref? --> Realist may ignore this warning.</dd> |
| 1316 |
|
</dl> |
| 1317 |
|
</d:item> |
| 1318 |
</d:item> |
</d:item> |
| 1319 |
|
|
| 1320 |
<d:item name="IMT:private subtype" |
<d:item name="IMT:private subtype" |
| 1356 |
|
|
| 1357 |
</section> |
</section> |
| 1358 |
|
|
| 1359 |
<section id="uri-warnings"> |
<section id="uri-shoulds"> |
| 1360 |
<h2>URI (or IRI) Warnings</h2> |
<h2>URI (or IRI) Should-level Errors</h2> |
| 1361 |
|
|
| 1362 |
<d:item name="URI::dot-segment" |
<d:item name="URI::dot-segment" |
| 1363 |
class="should" level="s"> |
class="should" level="s"> |
| 1364 |
<d:message xml:lang="en">Dot-segment (<code>.</code> or |
<d:message xml:lang="en">A dot-segment (<code>.</code> or |
| 1365 |
<code>..</code>) should not occur in an absolute reference.</d:message> |
<code>..</code>) occurs in an absolute reference.</d:message> |
| 1366 |
<d:desc> |
<d:desc> |
| 1367 |
<p>Dot-segment (<code>.</code> or <code>..</code>) should |
<p>Dot-segment (<code>.</code> or <code>..</code>) should |
| 1368 |
not occur in an absolute reference.</p> |
not occur in an absolute reference.</p> |
| 1377 |
|
|
| 1378 |
<d:item name="URI::empty path" |
<d:item name="URI::empty path" |
| 1379 |
class="should" level="s"> |
class="should" level="s"> |
| 1380 |
<d:message xml:lang="en">This IRI should explicitly end with |
<d:message xml:lang="en">This IRI does not end with |
| 1381 |
<code>/</code>.</d:message> |
a <code>/</code>.</d:message> |
| 1382 |
|
<d:item xml:lang="en"> |
| 1383 |
|
<p>The IRI does not end with a <code>/</code>. If there is an |
| 1384 |
|
authority component in an IRI, a <code>/</code> should be present |
| 1385 |
|
instead of empty path component.</p> |
| 1386 |
|
|
| 1387 |
|
<p>For example, <code>http://www.example.com<strong>/</strong></code> |
| 1388 |
|
is preferred to <code>http://www.example.com</code>.</p> |
| 1389 |
|
</d:item> |
| 1390 |
</d:item> |
</d:item> |
| 1391 |
|
|
| 1392 |
<d:item name="URI::lowercase hexadecimal digit" |
<d:item name="URI::lowercase hexadecimal digit" |
| 1393 |
class="should" level="s"> |
class="should" level="s"> |
| 1394 |
<d:message xml:lang="en">Hexadecimal digit in percent-encoding |
<d:message xml:lang="en">A lowercase hexadecimal digit is used |
| 1395 |
should be in lowercase.</d:message> |
in percent-encoding.</d:message> |
| 1396 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 1397 |
<p>The hexadecimal digit in percent-encoding string in the IRI |
<p>The hexadecimal digit in percent-encoding string in the IRI |
| 1398 |
is in lowercase. Though the IRI <em>is</em> conforming, |
is in lowercase. Though the IRI <em>is</em> conforming, |
| 1433 |
|
|
| 1434 |
</section> |
</section> |
| 1435 |
|
|
| 1436 |
|
<section id="cache-manifest-errors"> |
| 1437 |
|
<h2>Cache Manifest Errors</h2> |
| 1438 |
|
|
| 1439 |
|
<d:item name="not manifest" class="must" level="m"> |
| 1440 |
|
<d:message xml:lang="en">This document is not a cache manifest.</d:message> |
| 1441 |
|
<d:desc xml:lang="en"> |
| 1442 |
|
<p>The specified document is <em>not</em> a cache manifest. |
| 1443 |
|
The document is non-conforming.</p> |
| 1444 |
|
|
| 1445 |
|
<p>An entity labeled as Internet media type |
| 1446 |
|
<code>text/cache-manifest</code> must contain a cache manifest.</p> |
| 1447 |
|
|
| 1448 |
|
<p>A cache manifest must start with a line whose content is |
| 1449 |
|
<code class="manifest example">CACHE MANIFEST</code> |
| 1450 |
|
(exactly one space character between |
| 1451 |
|
<code>CACHE</code> and <code>MANIFEST</code>).</p> |
| 1452 |
|
</d:desc> |
| 1453 |
|
</d:item> |
| 1454 |
|
</section> |
| 1455 |
|
|
| 1456 |
<section id="unsupported-messages"> |
<section id="unsupported-messages"> |
| 1457 |
<h2><i>Unsupported</i> Messages</h2> |
<h2><i>Unsupported</i> Messages</h2> |
| 1458 |
|
|
| 1459 |
<d:item name="attribute" |
<d:item name="element" |
| 1460 |
class="unsupported" level="unsupported"> |
class="unsupported" level="unsupported"> |
| 1461 |
<d:message xml:lang="en">This attribute is not supported by the |
<d:message xml:lang="en">Conformance checking for element |
| 1462 |
conformance checker; <em>it might or might not be conforming</em>.</d:message> |
<code><var>{local-name}</var></code> is not supported; <em>it might or |
| 1463 |
|
might not be conforming</em>.</d:message> |
| 1464 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 1465 |
<p>The conformant checker does not support the attribute. |
<p>The conformant checker does not support the element. |
| 1466 |
It cannot determine whether the document is conforming or not.</p> |
It cannot determine whether the document is conforming or not.</p> |
| 1467 |
</d:desc> |
</d:desc> |
| 1468 |
</d:item> |
</d:item> |
| 1469 |
|
|
| 1470 |
<d:item name="element" |
<d:item name="attribute" |
| 1471 |
class="unsupported" level="unsupported"> |
class="unsupported" level="unsupported"> |
| 1472 |
<d:message xml:lang="en">This element is not supported by the |
<d:message xml:lang="en">Conformance checking for attribute |
| 1473 |
conformance checker; <em>it might or might not be conforming</em>.</d:message> |
<code><var>{local-name}</var></code> of element |
| 1474 |
|
<code><var>{element-local-name}</var></code> is not supported; |
| 1475 |
|
<em>it might or might not be conforming</em>.</d:message> |
| 1476 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 1477 |
<p>The conformant checker does not support the element. |
<p>The conformant checker does not support the attribute. |
| 1478 |
It cannot determine whether the document is conforming or not.</p> |
It cannot determine whether the document is conforming or not.</p> |
| 1479 |
</d:desc> |
</d:desc> |
| 1480 |
</d:item> |
</d:item> |
| 1481 |
|
|
| 1482 |
<d:item name="link type" |
<d:item name="link type" |
| 1483 |
class="unsupported" level="unsupported"> |
class="unsupported" level="unsupported"> |
| 1484 |
<d:message xml:lang="en">The link type <code><var>$0</var></code> is not |
<d:message xml:lang="en">Link type <code><var>$0</var></code> is not |
| 1485 |
standardized or registered at the time of the release of the conformance |
standardized or registered at the time of the release of the conformance |
| 1486 |
checker; <em>it is non-conforming unless it has now been |
checker; <em>it is non-conforming unless it now has been |
| 1487 |
registered</em>.</d:message> |
registered</em>.</d:message> |
| 1488 |
<d:desc xml:lang="en"> |
<d:desc xml:lang="en"> |
| 1489 |
<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. |
| 1496 |
The link type might have been added to the registry since then. |
The link type might have been added to the registry since then. |
| 1497 |
In such case it might be conforming. Otherwise, the |
In such case it might be conforming. Otherwise, the |
| 1498 |
document is non-conforming.</p> |
document is non-conforming.</p> |
| 1499 |
|
|
| 1500 |
|
<dl> |
| 1501 |
|
<dt>Link types <code>shortcut icon</code></dt> |
| 1502 |
|
<dd>Link type <code>shortcut</code> is not registered. |
| 1503 |
|
Use only <code>icon</code> for linking to so-called favicon.</dd> |
| 1504 |
|
</dl> |
| 1505 |
</d:desc> |
</d:desc> |
| 1506 |
</d:item> |
</d:item> |
| 1507 |
|
|
| 1511 |
is not supported; <em>it might or might not be conforming.</em></d:message> |
is not supported; <em>it might or might not be conforming.</em></d:message> |
| 1512 |
</d:item> |
</d:item> |
| 1513 |
|
|
|
<d:item name="language tag" |
|
|
class="unsupported" level="unsupported"> |
|
|
<d:message xml:lang="en">Conformance checking for language tag |
|
|
is not supported; <em>it might or might not be conforming.</em></d:message> |
|
|
</d:item> |
|
|
|
|
| 1514 |
<d:item name="media query" |
<d:item name="media query" |
| 1515 |
class="unsupported" level="unsupported"> |
class="unsupported" level="unsupported"> |
| 1516 |
<d:message xml:lang="en">Conformance checking for media query |
<d:message xml:lang="en">Conformance checking for media query |
| 1542 |
manakaiIsHTML:0;;XML Document |
manakaiIsHTML:0;;XML Document |
| 1543 |
</d:catalog> |
</d:catalog> |
| 1544 |
|
|
| 1545 |
|
<section id="levels"> |
| 1546 |
|
<h2>Error Levels</h2> |
| 1547 |
|
|
| 1548 |
|
<table id="levels-table"> |
| 1549 |
|
<thead> |
| 1550 |
|
<tr><th scope="col">Level</th> |
| 1551 |
|
<th scope="col">Conforming?</th> |
| 1552 |
|
<th scope="col">Description</th> |
| 1553 |
|
</tr> |
| 1554 |
|
</thead> |
| 1555 |
|
<tbody> |
| 1556 |
|
<tr id="level-m" class="level-m"> |
| 1557 |
|
<th scope="row"><em class="rfc2119">MUST</em>‐level error</th> |
| 1558 |
|
<td>Non‐conforming.</td> |
| 1559 |
|
<td>A violation to a hard requirement of the specification. |
| 1560 |
|
The document is non‐conforming.</td> |
| 1561 |
|
</tr> |
| 1562 |
|
<tr id="level-s" class="level-s"> |
| 1563 |
|
<th scope="row"><em class="rfc2119">SHOULD</em>‐level error</th> |
| 1564 |
|
<td>Non‐conforming, but <em>in some case</em> |
| 1565 |
|
conforming.</td> |
| 1566 |
|
<td>A violation to a requirement of the specification. |
| 1567 |
|
The violation might be legitimize in some case. Otherwise, |
| 1568 |
|
the document is non‐conforming.</td> |
| 1569 |
|
</tr> |
| 1570 |
|
<tr id="level-w" class="level-w"> |
| 1571 |
|
<th scope="row">Warning</th> |
| 1572 |
|
<td>Conforming.</td> |
| 1573 |
|
<td>A warning is an advice from the conformance checker to avoid |
| 1574 |
|
to solve a problem in a confusing or possibly wrong way. |
| 1575 |
|
It does not affect to the conformance of the document, and |
| 1576 |
|
may sometimes be inappropriate.</td> |
| 1577 |
|
</tr> |
| 1578 |
|
<tr id="level-u" class="level-u"> |
| 1579 |
|
<th scope="row">Not supported</th> |
| 1580 |
|
<td><em>Unknown</em>.</td> |
| 1581 |
|
<td>Some feature that is not supported by the conformance checker |
| 1582 |
|
is used in the document.</td> |
| 1583 |
|
</tr> |
| 1584 |
|
</tbody> |
| 1585 |
|
</table> |
| 1586 |
|
</section> |
| 1587 |
|
|
| 1588 |
<section id="license"> |
<section id="license"> |
| 1589 |
<h2>License of This Document</h2> |
<h2>License of This Document</h2> |
| 1590 |
|
|
| 1591 |
<p>Copyright 2007 <a href="http://suika.fam.cx/~wakaba/who?">Wakaba</a></p> |
<p>Copyright <time>2007</time> |
| 1592 |
<p>This library is free software; you can redistribute it |
<a href="http://suika.fam.cx/~wakaba/who?" rel="author" xml:lang="ja">Wakaba</a> |
| 1593 |
|
<code class="mail"><<a href="mailto:w@suika.fam.cx">w@suika.fam.cx</a>></code>.</p> |
| 1594 |
|
|
| 1595 |
|
<p>This document is free software; you can redistribute it |
| 1596 |
and/or modify it under the same terms as Perl itself.</p> |
and/or modify it under the same terms as Perl itself.</p> |
| 1597 |
</section> |
</section> |
| 1598 |
|
|