Mercurial > drafts / changeset

     1.1 --- a/selectors/Overview.bs	Mon Aug 11 14:30:47 2014 -0700
     1.2 +++ b/selectors/Overview.bs	Mon Aug 11 19:06:45 2014 -0700
     1.3 @@ -657,11 +657,11 @@
     1.4  		but not only elements with <a>shadow trees</a> have ''::shadow'' pseudo-elements.
     1.5  	</div>
     1.6  
     1.7 -	Four aspects of a DOM element are especially relevant for selectors:
     1.8 +	Five aspects of a DOM element are especially relevant for selectors:
     1.9  
    1.10  	<ul>
    1.11 -		<li>The element's type (also known as tagname),
    1.12 -			which is a pair of strings: a namespace and a local name.
    1.13 +		<li>The element's type (also known as tagname), which is a string.
    1.14 +		<li>The element's namespace, which is a string.
    1.15  		<li>An ID, which is a string.
    1.16  		<li>Classes, which are strings.
    1.17  		<li>Attributes, which are pairs of strings consisting of an attribute name and an attribute value.
    1.18 @@ -673,12 +673,12 @@
    1.19  	are called <dfn export title="feature selector">feature selectors</dfn>.
    1.20  
    1.21  	While elements may lack any of the individual <a>features</a>,
    1.22 -	some elements are <dfn export>featureless</dfn>,
    1.23 -	which means that not only do they lack any <a>features</a>
    1.24 -	(and thus will never match a <a>feature selector</a>),
    1.25 -	but any selectors that reference <a>features</a>,
    1.26 -	such as '':not(div)'',
    1.27 -	also never match them.
    1.28 +	some elements are <dfn export>featureless</dfn>.
    1.29 +	A <a>featureless</a> element does not match any <a>feature selector</a>,
    1.30 +	or any selector that resolves based on <a>features</a>
    1.31 +	(such as '':not(div)''),
    1.32 +	with the exception of namespace selectors--
    1.33 +	a <a>featureless</a> element is treated as having <em>all</em> namespaces.
    1.34  	Thus, only <a>pseudo-classes</a> or <a>pseudo-elements</a> can be used to select them.
    1.35  	Individual <a>featureless</a> elements may define additional restrictions on what kinds of selectors can match them.
    1.36  
    1.37 @@ -687,6 +687,25 @@
    1.38  		and can't be matched by <em>any</em> <a>pseudo-class</a> except for '':host'' and '':host-context()''.)
    1.39  	</div>
    1.40  
    1.41 +	<details class='why'>
    1.42 +		<summary>Why do featureless elements match all namespaces?</summary>
    1.43 +
    1.44 +		In a previous version of Selectors,
    1.45 +		all <a>compound selectors</a> contained a <a>type selector</a>;
    1.46 +		if you didn't supply one explicitly,
    1.47 +		a <a>universal selector</a> was implied.
    1.48 +		Default namespaces [[CSS3NAMESPACE]] affected the implied universal selector,
    1.49 +		so that selectors like '':hover'' actually meant ''defaultNS|*:hover''.
    1.50 +
    1.51 +		The universal selector is no longer implied,
    1.52 +		but default namespaces still exist,
    1.53 +		and have to apply to all compound selectors.
    1.54 +		The behavior of <a>featureless</a> elements,
    1.55 +		like the <a>host element</a> in a shadow tree,
    1.56 +		thus needs to accommodate that and work appropriately.
    1.57 +		In this case, "appropriately" means "ignoring the default namespace".
    1.58 +	</details>
    1.59 +
    1.60  	When matching a selector against a document which is in <a>quirks mode</a>,
    1.61  	class and ID selectors must be matched <a title="ASCII case-insensitive">ASCII case-insensitively</a>
    1.62  	against the classes and ID of the elements in the document.
    1.63 @@ -724,9 +743,9 @@
    1.64  
    1.65  			If this "type" can be separated into a "basic" name
    1.66  			and a "namespace" that groups names into higher-level groups,
    1.67 -			that should be reflected in the "namespace" and "local name" divisions of the "type" <a>feature</a>.
    1.68 -			Otherwise, the "namespace" part should be the empty string,
    1.69 -			and the entire name should be in the "local name" part.
    1.70 +			the latter should be reflected as the "namespace" <a>feature</a>.
    1.71 +			Otherwise, the element shouldn't have a "namespace" <a>feature</a>,
    1.72 +			and the entire name should be reflected as the "type" <a>feature</a>.
    1.73  
    1.74  		<dt>id
    1.75  		<dd>
    1.76 @@ -1203,8 +1222,11 @@
    1.77  	Pseudo-elements cannot be represented by the matches-any pseudo-class;
    1.78  	they are not valid within '':matches()''.
    1.79  
    1.80 -	Default namespace declarations do not affect any “implied” universal selectors
    1.81 -	within a '':matches()'' pseudo-class.
    1.82 +	Within a '':matches()'' pseudo-class,
    1.83 +	default namespace declarations only have an effect on compound selectors
    1.84 +	that contain a <a>type selector</a>.
    1.85 +
    1.86 +	Issue: Do we want to extend this protection from default namespaces to other things?
    1.87  
    1.88  	<div class="example">
    1.89  		For example, the following selector matches any element that is being
    1.90 @@ -1301,51 +1323,62 @@
    1.91  Type (tag name) selector</h3>
    1.92  
    1.93  	A <dfn export>type selector</dfn> is the name of a document language element type
    1.94 -	written using the syntax of <a href="http://www.w3.org/TR/css3-namespace/#css-qnames">CSS qualified names</a> [[!CSS3NAMESPACE]].
    1.95 +	written as either an <a>identifier</a>
    1.96 +	or, if interacting with namespaces,
    1.97 +	a <a>CSS qualified name</a>
    1.98 +	(see [[#type-nmsp]])
    1.99 +	[[!CSS3NAMESPACE]].
   1.100 +
   1.101  	A type selector represents an instance of the element type in the document tree.
   1.102  
   1.103  	<div class="example">
   1.104 -	 Example:
   1.105 -	 The following selector represents an <a element>h1</a> element in the document tree:
   1.106 -
   1.107 -	 <pre>h1 </pre>
   1.108 +		For example, the selector ''h1'' represents an <a element>h1</a> element in the document.
   1.109  	</div>
   1.110  
   1.111 -<h4 id="typenmsp">
   1.112 -Type selectors and namespaces</h4>
   1.113 -
   1.114 -	Type selectors allow an optional namespace component: a namespace
   1.115 -	prefix that has been previously <a href="#nsdecl">declared</a> may be
   1.116 -	prepended to the element name separated by the namespace separator
   1.117 -	&quot;vertical bar&quot; (U+007C, <code>|</code>). (See, e.g., [[XML-NAMES]] for the use of namespaces in
   1.118 -	XML.)
   1.119 -
   1.120 -	The namespace component may be left empty (no prefix before the
   1.121 -	namespace separator) to indicate that the selector is only to
   1.122 -	represent elements with no namespace.
   1.123 -
   1.124 -	An asterisk may be used for the namespace prefix, indicating that
   1.125 -	the selector represents elements in any namespace (including elements
   1.126 -	with no namespace).
   1.127 -
   1.128 -	Element type selectors that have no namespace component (no
   1.129 -	namespace separator) represent elements without regard to the
   1.130 -	element's namespace (equivalent to "<code>*|</code>") unless a default
   1.131 -	namespace has been <a href="#nsdecl">declared</a>  for namespaced selectors (e.g. in CSS, in
   1.132 -	the style sheet). If a default namespace has been declared, such
   1.133 -	selectors will represent only elements in the default namespace.
   1.134 -
   1.135 -	A type selector containing a namespace prefix that has not been
   1.136 -	previously <a href="#nsdecl">declared</a> for namespaced selectors is
   1.137 -	an <a href="#conformance">invalid</a> selector.
   1.138 -
   1.139 -	In a namespace-aware client,
   1.140 -	the name part of element type selectors
   1.141 -	(the part after the namespace separator, if it is present)
   1.142 -	will only match against the <a href="http://www.w3.org/TR/REC-xml-names/#NT-LocalPart">local part</a>
   1.143 -	of the element's <a href="http://www.w3.org/TR/REC-xml-names/#ns-qualnames">qualified name</a>.
   1.144 -
   1.145 -	In summary:
   1.146 +<h3 id="the-universal-selector">
   1.147 +Universal selector </h3>
   1.148 +
   1.149 +	The <dfn export>universal selector</dfn> is a special <a>type selector</a>,
   1.150 +	written either as the asterisk character (<code>*</code> U+002A),
   1.151 +	or as a <a>CSS qualified name</a>
   1.152 +	with an asterisk as the local name (see [[#type-nmsp]]).
   1.153 +	It represents an element with any name.
   1.154 +
   1.155 +	Like a <a>type selector</a>,
   1.156 +	the <a>universal selector</a> can be qualified by a namespace,
   1.157 +	and is affected by a default namespace as defined in [[#type-nmsp]].
   1.158 +
   1.159 +	Unless an element is <a>featureless</a>,
   1.160 +	the presence of a <a>universal selector</a> has no effect on whether the element matches the selector.
   1.161 +	(<a>Featureless</a> elements do not match any <a>feature</a> selector,
   1.162 +		including the <a>universal selector</a>.)
   1.163 +
   1.164 +	<div class="example">
   1.165 +		<ul>
   1.166 +			<li>
   1.167 +				<span class=css>*[hreflang|=en]</span> and <span class=css>[hreflang|=en]</span> are equivalent,
   1.168 +			<li>''*.warning'' and ''.warning'' are equivalent,
   1.169 +			<li>''*#myid'' and ''#myid'' are equivalent.
   1.170 +		</ul>
   1.171 +	</div>
   1.172 +
   1.173 +	The <a>universal selector</a> follows the same syntax rules as other <a>type selectors</a>:
   1.174 +	only one can appear per <a>compound selector</a>,
   1.175 +	and it must be the first <a>simple selector</a> in the <a>compound selector</a>.
   1.176 +
   1.177 +	Note: In some cases, adding a <a>universal selector</a> can make a selector easier to read,
   1.178 +	even though it has no effect on the matching behavior.
   1.179 +	For example, ''div :first-child'' and ''div:first-child'' are somewhat difficult to tell apart at a quick glance,
   1.180 +	but writing the former as ''div *:first-child'' makes the difference obvious.
   1.181 +
   1.182 +<h3 id='type-nmsp'>
   1.183 +Namespaces in Selectors</h3>
   1.184 +
   1.185 +	<a>Type selectors</a> allow an optional namespace component:
   1.186 +	a namespace prefix that has been previously <a href="#nsdecl">declared</a>
   1.187 +	may be prepended to the element name separated by the namespace separator “vertical bar” (<code>|</code> U+007C).
   1.188 +	(See, e.g., [[XML-NAMES]] for the use of namespaces in XML.)
   1.189 +	It has the following meaning in each form:
   1.190  
   1.191  	<dl>
   1.192  		<dt><code>ns|E</code>
   1.193 @@ -1398,71 +1431,24 @@
   1.194  		namespace has been defined.
   1.195  	</div>
   1.196  
   1.197 -<h3 id="the-universal-selector">
   1.198 -Universal selector </h3>
   1.199 -
   1.200 -	The <dfn export>universal selector</dfn>, written as a
   1.201 -	<a href="http://www.w3.org/TR/css3-namespace/#css-qnames">CSS qualified
   1.202 -	name</a> [[!CSS3NAMESPACE]] with an asterisk (<code>*</code>
   1.203 -	U+002A) as the local name, represents the qualified name of any element
   1.204 -	type. It represents any single element in the document tree in any
   1.205 -	namespace (including those without a namespace) if no default
   1.206 -	namespace has been specified for selectors. If a default namespace has
   1.207 -	been specified, see <a href="#univnmsp">Universal selector and
   1.208 -	Namespaces</a> below.
   1.209 -
   1.210 -	If a universal selector represented by ''*''
   1.211 -	(i.e. without a namespace prefix)
   1.212 -	is not the only component of a <a>compound selector</a>
   1.213 -	or is immediately followed by a <a>pseudo-element</a>,
   1.214 -	then the ''*'' may be omitted
   1.215 -	and the universal selector's presence implied.
   1.216 -
   1.217 -	<div class="example">
   1.218 -		<ul>
   1.219 -			<li>''*[hreflang|=en]'' and ''[hreflang|=en]'' are equivalent,
   1.220 -			<li>''*.warning'' and ''.warning'' are equivalent,
   1.221 -			<li>''*#myid'' and ''#myid'' are equivalent.
   1.222 -		</ul>
   1.223 +	If a <a>default namespace</a> is declared,
   1.224 +	<a>compound selectors</a> without <a>type selectors</a> in them
   1.225 +	still only match elements in that default namespace.
   1.226 +
   1.227 +	<div class='example'>
   1.228 +		For example,
   1.229 +		in the following stylesheet:
   1.230 +
   1.231 +		<pre>
   1.232 +		@namespace url("http://example.com/foo");
   1.233 +
   1.234 +		.special { ... }
   1.235 +		</pre>
   1.236 +
   1.237 +		The ''.special'' selector only matches elements in the "http://example.com/foo" namespace,
   1.238 +		even though no reference to the type name (which is paired with the namespace in the DOM) appeared.
   1.239  	</div>
   1.240  
   1.241 -	Note: It is recommended that the ''*'' not be omitted,
   1.242 -	because it decreases the potential confusion between,
   1.243 -	for example, ''div :first-child''
   1.244 -	and ''div:first-child''.
   1.245 -	Here, ''div *:first-child'' is more readable.
   1.246 -
   1.247 -<h4 id="univnmsp">
   1.248 -Universal selector and namespaces</h4>
   1.249 -
   1.250 -	The universal selector allows an optional namespace component. It
   1.251 -	is used as follows:
   1.252 -
   1.253 -	<dl>
   1.254 -		<dt>''ns|*''
   1.255 -		<dd>
   1.256 -			all elements in namespace ns
   1.257 -
   1.258 -		<dt>''*|*''
   1.259 -		<dd>
   1.260 -			all elements
   1.261 -
   1.262 -		<dt>''|*''
   1.263 -		<dd>
   1.264 -			all elements without a namespace
   1.265 -
   1.266 -		<dt>''*''
   1.267 -		<dd>
   1.268 -			if no default namespace has been specified,
   1.269 -			this is equivalent to *|*.
   1.270 -			Otherwise it is equivalent to ns|*
   1.271 -			where ns is the default namespace.
   1.272 -	</dl>
   1.273 -
   1.274 -	A universal selector containing a namespace prefix
   1.275 -	that has not been previously <a href="#nsdecl">declared</a>
   1.276 -	is an <a>invalid selector</a>.
   1.277 -
   1.278  
   1.279  <h2 id="attribute-selectors">
   1.280  Attribute selectors</h2>

     2.1 --- a/selectors/Overview.html	Mon Aug 11 14:30:47 2014 -0700
     2.2 +++ b/selectors/Overview.html	Mon Aug 11 19:06:45 2014 -0700
     2.3 @@ -59,7 +59,7 @@
     2.4  </p>
     2.5    <h1 class="p-name no-ref" id=title>Selectors Level 4</h1>
     2.6    <h2 class="no-num no-toc no-ref heading settled heading" id=subtitle><span class=content>Editor’s Draft,
     2.7 -    <span class=dt-updated><span class=value-title title=20140808>8 August 2014</span></span></span></h2>
     2.8 +    <span class=dt-updated><span class=value-title title=20140812>12 August 2014</span></span></span></h2>
     2.9    <div data-fill-with=spec-metadata><dl>
    2.10  	<dt>This version:
    2.11  	<dd><a class=u-url href=http://dev.w3.org/csswg/selectors>http://dev.w3.org/csswg/selectors</a>
    2.12 @@ -166,11 +166,8 @@
    2.13  	<li><a href=#elemental-selectors><span class=secno>5</span>  Elemental selectors</a>
    2.14  		<ul class=toc>
    2.15  		<li><a href=#type-selectors><span class=secno>5.1</span>  Type (tag name) selector</a>
    2.16 -			<ul class=toc>
    2.17 -			<li><a href=#typenmsp><span class=secno>5.1.1</span>  Type selectors and namespaces</a></ul>
    2.18  		<li><a href=#the-universal-selector><span class=secno>5.2</span>  Universal selector </a>
    2.19 -			<ul class=toc>
    2.20 -			<li><a href=#univnmsp><span class=secno>5.2.1</span>  Universal selector and namespaces</a></ul></ul>
    2.21 +		<li><a href=#type-nmsp><span class=secno>5.3</span>  Namespaces in Selectors</a></ul>
    2.22  	<li><a href=#attribute-selectors><span class=secno>6</span>  Attribute selectors</a>
    2.23  		<ul class=toc>
    2.24  		<li><a href=#attribute-representation><span class=secno>6.1</span>  Attribute presence and value selectors</a>
    2.25 @@ -903,11 +900,11 @@
    2.26  		but not only elements with <a data-link-type=dfn href=http://dev.w3.org/csswg/css-scoping-1/#shadow-tree title="shadow trees">shadow trees</a> have <a class=css data-link-type=maybe href=http://dev.w3.org/csswg/css-scoping-1/#selectordef-shadow title=::shadow>::shadow</a> pseudo-elements.</p>
    2.27  	</div>
    2.28  
    2.29 -<p>Four aspects of a DOM element are especially relevant for selectors:</p>
    2.30 +<p>Five aspects of a DOM element are especially relevant for selectors:</p>
    2.31  
    2.32  	<ul>
    2.33 -		<li>The element’s type (also known as tagname),
    2.34 -			which is a pair of strings: a namespace and a local name.
    2.35 +		<li>The element’s type (also known as tagname), which is a string.
    2.36 +		<li>The element’s namespace, which is a string.
    2.37  		<li>An ID, which is a string.
    2.38  		<li>Classes, which are strings.
    2.39  		<li>Attributes, which are pairs of strings consisting of an attribute name and an attribute value.
    2.40 @@ -919,12 +916,11 @@
    2.41  	are called <dfn data-dfn-type=dfn data-export="" id=feature-selector title="feature selector">feature selectors<a class=self-link href=#feature-selector></a></dfn>.</p>
    2.42  
    2.43  <p>While elements may lack any of the individual <a data-link-type=dfn href=#feature title=features>features</a>,
    2.44 -	some elements are <dfn data-dfn-type=dfn data-export="" id=featureless>featureless<a class=self-link href=#featureless></a></dfn>,
    2.45 -	which means that not only do they lack any <a data-link-type=dfn href=#feature title=features>features</a>
    2.46 -	(and thus will never match a <a data-link-type=dfn href=#feature-selector title="feature selector">feature selector</a>),
    2.47 -	but any selectors that reference <a data-link-type=dfn href=#feature title=features>features</a>,
    2.48 -	such as <span class=css data-link-type=maybe title=:not(div)>:not(div)</span>,
    2.49 -	also never match them.
    2.50 +	some elements are <dfn data-dfn-type=dfn data-export="" id=featureless>featureless<a class=self-link href=#featureless></a></dfn>.
    2.51 +	A <a data-link-type=dfn href=#featureless title=featureless>featureless</a> element does not match any <a data-link-type=dfn href=#feature-selector title="feature selector">feature selector</a>,
    2.52 +	or any selector that resolves based on <a data-link-type=dfn href=#feature title=features>features</a>
    2.53 +	(such as <span class=css data-link-type=maybe title=:not(div)>:not(div)</span>),
    2.54 +	with the exception of namespace selectors—<wbr>a <a data-link-type=dfn href=#featureless title=featureless>featureless</a> element is treated as having <em>all</em> namespaces.
    2.55  	Thus, only <a data-link-type=dfn href=#pseudo-class title=pseudo-classes>pseudo-classes</a> or <a data-link-type=dfn href=#pseudo-element title=pseudo-elements>pseudo-elements</a> can be used to select them.
    2.56  	Individual <a data-link-type=dfn href=#featureless title=featureless>featureless</a> elements may define additional restrictions on what kinds of selectors can match them.</p>
    2.57  
    2.58 @@ -933,6 +929,25 @@
    2.59  		and can’t be matched by <em>any</em> <a data-link-type=dfn href=#pseudo-class title=pseudo-class>pseudo-class</a> except for <a class=css data-link-type=maybe href=http://dev.w3.org/csswg/css-scoping-1/#selectordef-host0 title=:host>:host</a> and <a class=css data-link-type=maybe href=http://dev.w3.org/csswg/css-scoping-1/#selectordef-host-context title=:host-context()>:host-context()</a>.)
    2.60  	</div>
    2.61  
    2.62 +	<details class=why>
    2.63 +		<summary>Why do featureless elements match all namespaces?</summary>
    2.64 +
    2.65 +<p>In a previous version of Selectors,
    2.66 +		all <a data-link-type=dfn href=#compound title="compound selectors">compound selectors</a> contained a <a data-link-type=dfn href=#type-selector title="type selector">type selector</a>;
    2.67 +		if you didn’t supply one explicitly,
    2.68 +		a <a data-link-type=dfn href=#universal-selector title="universal selector">universal selector</a> was implied.
    2.69 +		Default namespaces <a data-biblio-type=informative data-link-type=biblio href=#biblio-css3namespace title=biblio-CSS3NAMESPACE>[CSS3NAMESPACE]</a> affected the implied universal selector,
    2.70 +		so that selectors like <a class=css data-link-type=maybe href=#hover-pseudo title=:hover>:hover</a> actually meant <span class=css data-link-type=maybe title=defaultNS|*:hover>defaultNS|*:hover</span>.</p>
    2.71 +
    2.72 +<p>The universal selector is no longer implied,
    2.73 +		but default namespaces still exist,
    2.74 +		and have to apply to all compound selectors.
    2.75 +		The behavior of <a data-link-type=dfn href=#featureless title=featureless>featureless</a> elements,
    2.76 +		like the <a data-link-type=dfn href=http://dev.w3.org/csswg/css-scoping-1/#host-element0 title="host element">host element</a> in a shadow tree,
    2.77 +		thus needs to accommodate that and work appropriately.
    2.78 +		In this case, "appropriately" means "ignoring the default namespace".</p>
    2.79 +	</details>
    2.80 +
    2.81  <p>When matching a selector against a document which is in <a data-link-type=dfn title="quirks mode">quirks mode</a>,
    2.82  	class and ID selectors must be matched <a data-link-type=dfn href=http://dev.w3.org/csswg/css-syntax-3/#ascii-case-insensitive title="ASCII case-insensitive">ASCII case-insensitively</a>
    2.83  	against the classes and ID of the elements in the document.</p>
    2.84 @@ -968,9 +983,9 @@
    2.85  
    2.86  <p>If this "type" can be separated into a "basic" name
    2.87  			and a "namespace" that groups names into higher-level groups,
    2.88 -			that should be reflected in the "namespace" and "local name" divisions of the "type" <a data-link-type=dfn href=#feature title=feature>feature</a>.
    2.89 -			Otherwise, the "namespace" part should be the empty string,
    2.90 -			and the entire name should be in the "local name" part.</p>
    2.91 +			the latter should be reflected as the "namespace" <a data-link-type=dfn href=#feature title=feature>feature</a>.
    2.92 +			Otherwise, the element shouldn’t have a "namespace" <a data-link-type=dfn href=#feature title=feature>feature</a>,
    2.93 +			and the entire name should be reflected as the "type" <a data-link-type=dfn href=#feature title=feature>feature</a>.</p>
    2.94  
    2.95  		<dt>id
    2.96  		<dd>
    2.97 @@ -1445,8 +1460,11 @@
    2.98  <p>Pseudo-elements cannot be represented by the matches-any pseudo-class;
    2.99  	they are not valid within <a class=css data-link-type=maybe href=#matches-pseudo title=:matches()>:matches()</a>.</p>
   2.100  
   2.101 -<p>Default namespace declarations do not affect any “implied” universal selectors
   2.102 -	within a <a class=css data-link-type=maybe href=#matches-pseudo title=:matches()>:matches()</a> pseudo-class.</p>
   2.103 +<p>Within a <a class=css data-link-type=maybe href=#matches-pseudo title=:matches()>:matches()</a> pseudo-class,
   2.104 +	default namespace declarations only have an effect on compound selectors
   2.105 +	that contain a <a data-link-type=dfn href=#type-selector title="type selector">type selector</a>.</p>
   2.106 +
   2.107 +<p class=issue id=issue-fdaebe5f><a class=self-link href=#issue-fdaebe5f></a>Do we want to extend this protection from default namespaces to other things?</p>
   2.108  
   2.109  	<div class=example>
   2.110  		For example, the following selector matches any element that is being
   2.111 @@ -1543,51 +1561,65 @@
   2.112  Type (tag name) selector</span><a class=self-link href=#type-selectors></a></h3>
   2.113  
   2.114  <p>A <dfn data-dfn-type=dfn data-export="" id=type-selector>type selector<a class=self-link href=#type-selector></a></dfn> is the name of a document language element type
   2.115 -	written using the syntax of <a href=http://www.w3.org/TR/css3-namespace/#css-qnames>CSS qualified names</a> <a data-biblio-type=normative data-link-type=biblio href=#biblio-css3namespace title=biblio-CSS3NAMESPACE>[CSS3NAMESPACE]</a>.
   2.116 -	A type selector represents an instance of the element type in the document tree.</p>
   2.117 +	written as either an <a data-link-type=dfn href=http://dev.w3.org/csswg/css-syntax-3/#identifier title=identifier>identifier</a>
   2.118 +	or, if interacting with namespaces,
   2.119 +	a <a data-link-type=dfn href=http://dev.w3.org/csswg/css-namespaces-1/#css-qualified-name title="CSS qualified name">CSS qualified name</a>
   2.120 +	(see <a data-section="" href=#type-nmsp>§5.3 
   2.121 +Namespaces in Selectors</a>)
   2.122 +	<a data-biblio-type=normative data-link-type=biblio href=#biblio-css3namespace title=biblio-CSS3NAMESPACE>[CSS3NAMESPACE]</a>.</p>
   2.123 +
   2.124 +<p>A type selector represents an instance of the element type in the document tree.</p>
   2.125  
   2.126  	<div class=example>
   2.127 -	 Example:
   2.128 -	 The following selector represents an <a data-link-type=element title=h1>h1</a> element in the document tree:
   2.129 -
   2.130 -<pre>h1 </pre>
   2.131 +		For example, the selector <span class=css data-link-type=maybe title=h1>h1</span> represents an <a data-link-type=element title=h1>h1</a> element in the document.
   2.132  	</div>
   2.133  
   2.134 -<h4 class="heading settled heading" data-level=5.1.1 id=typenmsp><span class=secno>5.1.1 </span><span class=content>
   2.135 -Type selectors and namespaces</span><a class=self-link href=#typenmsp></a></h4>
   2.136 -
   2.137 -<p>Type selectors allow an optional namespace component: a namespace
   2.138 -	prefix that has been previously <a href=#nsdecl>declared</a> may be
   2.139 -	prepended to the element name separated by the namespace separator
   2.140 -	"vertical bar" (U+007C, <code>|</code>). (See, e.g., <a data-biblio-type=informative data-link-type=biblio href=#biblio-xml-names title=biblio-XML-NAMES>[XML-NAMES]</a> for the use of namespaces in
   2.141 -	XML.)</p>
   2.142 -
   2.143 -<p>The namespace component may be left empty (no prefix before the
   2.144 -	namespace separator) to indicate that the selector is only to
   2.145 -	represent elements with no namespace.</p>
   2.146 -
   2.147 -<p>An asterisk may be used for the namespace prefix, indicating that
   2.148 -	the selector represents elements in any namespace (including elements
   2.149 -	with no namespace).</p>
   2.150 -
   2.151 -<p>Element type selectors that have no namespace component (no
   2.152 -	namespace separator) represent elements without regard to the
   2.153 -	element’s namespace (equivalent to "<code>*|</code>") unless a default
   2.154 -	namespace has been <a href=#nsdecl>declared</a>  for namespaced selectors (e.g. in CSS, in
   2.155 -	the style sheet). If a default namespace has been declared, such
   2.156 -	selectors will represent only elements in the default namespace.</p>
   2.157 -
   2.158 -<p>A type selector containing a namespace prefix that has not been
   2.159 -	previously <a href=#nsdecl>declared</a> for namespaced selectors is
   2.160 -	an <a href=#conformance>invalid</a> selector.</p>
   2.161 -
   2.162 -<p>In a namespace-aware client,
   2.163 -	the name part of element type selectors
   2.164 -	(the part after the namespace separator, if it is present)
   2.165 -	will only match against the <a href=http://www.w3.org/TR/REC-xml-names/#NT-LocalPart>local part</a>
   2.166 -	of the element’s <a href=http://www.w3.org/TR/REC-xml-names/#ns-qualnames>qualified name</a>.</p>
   2.167 -
   2.168 -<p>In summary:</p>
   2.169 +<h3 class="heading settled heading" data-level=5.2 id=the-universal-selector><span class=secno>5.2 </span><span class=content>
   2.170 +Universal selector </span><a class=self-link href=#the-universal-selector></a></h3>
   2.171 +
   2.172 +<p>The <dfn data-dfn-type=dfn data-export="" id=universal-selector>universal selector<a class=self-link href=#universal-selector></a></dfn> is a special <a data-link-type=dfn href=#type-selector title="type selector">type selector</a>,
   2.173 +	written either as the asterisk character (<code>*</code> U+002A),
   2.174 +	or as a <a data-link-type=dfn href=http://dev.w3.org/csswg/css-namespaces-1/#css-qualified-name title="CSS qualified name">CSS qualified name</a>
   2.175 +	with an asterisk as the local name (see <a data-section="" href=#type-nmsp>§5.3 
   2.176 +Namespaces in Selectors</a>).
   2.177 +	It represents an element with any name.</p>
   2.178 +
   2.179 +<p>Like a <a data-link-type=dfn href=#type-selector title="type selector">type selector</a>,
   2.180 +	the <a data-link-type=dfn href=#universal-selector title="universal selector">universal selector</a> can be qualified by a namespace,
   2.181 +	and is affected by a default namespace as defined in <a data-section="" href=#type-nmsp>§5.3 
   2.182 +Namespaces in Selectors</a>.</p>
   2.183 +
   2.184 +<p>Unless an element is <a data-link-type=dfn href=#featureless title=featureless>featureless</a>,
   2.185 +	the presence of a <a data-link-type=dfn href=#universal-selector title="universal selector">universal selector</a> has no effect on whether the element matches the selector.
   2.186 +	(<a data-link-type=dfn href=#featureless title=Featureless>Featureless</a> elements do not match any <a data-link-type=dfn href=#feature title=feature>feature</a> selector,
   2.187 +		including the <a data-link-type=dfn href=#universal-selector title="universal selector">universal selector</a>.)</p>
   2.188 +
   2.189 +	<div class=example>
   2.190 +		<ul>
   2.191 +			<li>
   2.192 +				<span class=css>*[hreflang|=en]</span> and <span class=css>[hreflang|=en]</span> are equivalent,
   2.193 +			<li><span class=css data-link-type=maybe title=*.warning>*.warning</span> and <span class=css data-link-type=maybe title=.warning>.warning</span> are equivalent,
   2.194 +			<li><span class=css data-link-type=maybe title=*#myid>*#myid</span> and <span class=css data-link-type=maybe title=#myid>#myid</span> are equivalent.
   2.195 +		</ul>
   2.196 +	</div>
   2.197 +
   2.198 +<p>The <a data-link-type=dfn href=#universal-selector title="universal selector">universal selector</a> follows the same syntax rules as other <a data-link-type=dfn href=#type-selector title="type selectors">type selectors</a>:
   2.199 +	only one can appear per <a data-link-type=dfn href=#compound title="compound selector">compound selector</a>,
   2.200 +	and it must be the first <a data-link-type=dfn href=#simple title="simple selector">simple selector</a> in the <a data-link-type=dfn href=#compound title="compound selector">compound selector</a>.</p>
   2.201 +
   2.202 +<p class=note>Note: In some cases, adding a <a data-link-type=dfn href=#universal-selector title="universal selector">universal selector</a> can make a selector easier to read,
   2.203 +	even though it has no effect on the matching behavior.
   2.204 +	For example, <span class=css data-link-type=maybe title="div :first-child">div :first-child</span> and <span class=css data-link-type=maybe title=div:first-child>div:first-child</span> are somewhat difficult to tell apart at a quick glance,
   2.205 +	but writing the former as <span class=css data-link-type=maybe title="div *:first-child">div *:first-child</span> makes the difference obvious.</p>
   2.206 +
   2.207 +<h3 class="heading settled heading" data-level=5.3 id=type-nmsp><span class=secno>5.3 </span><span class=content>
   2.208 +Namespaces in Selectors</span><a class=self-link href=#type-nmsp></a></h3>
   2.209 +
   2.210 +<p><a data-link-type=dfn href=#type-selector title="Type selectors">Type selectors</a> allow an optional namespace component:
   2.211 +	a namespace prefix that has been previously <a href=#nsdecl>declared</a>
   2.212 +	may be prepended to the element name separated by the namespace separator “vertical bar” (<code>|</code> U+007C).
   2.213 +	(See, e.g., <a data-biblio-type=informative data-link-type=biblio href=#biblio-xml-names title=biblio-XML-NAMES>[XML-NAMES]</a> for the use of namespaces in XML.)
   2.214 +	It has the following meaning in each form:</p>
   2.215  
   2.216  	<dl>
   2.217  		<dt><code>ns|E</code>
   2.218 @@ -1639,71 +1671,22 @@
   2.219  		namespace has been defined.</p>
   2.220  	</div>
   2.221  
   2.222 -<h3 class="heading settled heading" data-level=5.2 id=the-universal-selector><span class=secno>5.2 </span><span class=content>
   2.223 -Universal selector </span><a class=self-link href=#the-universal-selector></a></h3>
   2.224 -
   2.225 -<p>The <dfn data-dfn-type=dfn data-export="" id=universal-selector>universal selector<a class=self-link href=#universal-selector></a></dfn>, written as a
   2.226 -	<a href=http://www.w3.org/TR/css3-namespace/#css-qnames>CSS qualified
   2.227 -	name</a> <a data-biblio-type=normative data-link-type=biblio href=#biblio-css3namespace title=biblio-CSS3NAMESPACE>[CSS3NAMESPACE]</a> with an asterisk (<code>*</code>
   2.228 -	U+002A) as the local name, represents the qualified name of any element
   2.229 -	type. It represents any single element in the document tree in any
   2.230 -	namespace (including those without a namespace) if no default
   2.231 -	namespace has been specified for selectors. If a default namespace has
   2.232 -	been specified, see <a href=#univnmsp>Universal selector and
   2.233 -	Namespaces</a> below.</p>
   2.234 -
   2.235 -<p>If a universal selector represented by <span class=css data-link-type=maybe title=*>*</span>
   2.236 -	(i.e. without a namespace prefix)
   2.237 -	is not the only component of a <a data-link-type=dfn href=#compound title="compound selector">compound selector</a>
   2.238 -	or is immediately followed by a <a data-link-type=dfn href=#pseudo-element title=pseudo-element>pseudo-element</a>,
   2.239 -	then the <span class=css data-link-type=maybe title=*>*</span> may be omitted
   2.240 -	and the universal selector’s presence implied.</p>
   2.241 +<p>If a <a data-link-type=dfn href=http://dev.w3.org/csswg/css-namespaces-1/#default-namespace title="default namespace">default namespace</a> is declared,
   2.242 +	<a data-link-type=dfn href=#compound title="compound selectors">compound selectors</a> without <a data-link-type=dfn href=#type-selector title="type selectors">type selectors</a> in them
   2.243 +	still only match elements in that default namespace.</p>
   2.244  
   2.245  	<div class=example>
   2.246 -		<ul>
   2.247 -			<li>''*[hreflang|=en]<span class=css data-link-type=maybe title=" and "> and </span>[hreflang|=en]'' are equivalent,
   2.248 -			<li><span class=css data-link-type=maybe title=*.warning>*.warning</span> and <span class=css data-link-type=maybe title=.warning>.warning</span> are equivalent,
   2.249 -			<li><span class=css data-link-type=maybe title=*#myid>*#myid</span> and <span class=css data-link-type=maybe title=#myid>#myid</span> are equivalent.
   2.250 -		</ul>
   2.251 +		For example,
   2.252 +		in the following stylesheet:
   2.253 +
   2.254 +		<pre>@namespace url("http://example.com/foo");
   2.255 +.special { ... }
   2.256 +</pre>
   2.257 +
   2.258 +<p>The <span class=css data-link-type=maybe title=.special>.special</span> selector only matches elements in the "http://example.com/foo" namespace,
   2.259 +		even though no reference to the type name (which is paired with the namespace in the DOM) appeared.</p>
   2.260  	</div>
   2.261  
   2.262 -<p class=note>Note: It is recommended that the <span class=css data-link-type=maybe title=*>*</span> not be omitted,
   2.263 -	because it decreases the potential confusion between,
   2.264 -	for example, <span class=css data-link-type=maybe title="div :first-child">div :first-child</span>
   2.265 -	and <span class=css data-link-type=maybe title=div:first-child>div:first-child</span>.
   2.266 -	Here, <span class=css data-link-type=maybe title="div *:first-child">div *:first-child</span> is more readable.</p>
   2.267 -
   2.268 -<h4 class="heading settled heading" data-level=5.2.1 id=univnmsp><span class=secno>5.2.1 </span><span class=content>
   2.269 -Universal selector and namespaces</span><a class=self-link href=#univnmsp></a></h4>
   2.270 -
   2.271 -<p>The universal selector allows an optional namespace component. It
   2.272 -	is used as follows:</p>
   2.273 -
   2.274 -	<dl>
   2.275 -		<dt><span class=css data-link-type=maybe title=ns|*>ns|*</span>
   2.276 -		<dd>
   2.277 -			all elements in namespace ns
   2.278 -
   2.279 -		<dt><span class=css data-link-type=maybe title=*|*>*|*</span>
   2.280 -		<dd>
   2.281 -			all elements
   2.282 -
   2.283 -		<dt><span class=css data-link-type=maybe title=|*>|*</span>
   2.284 -		<dd>
   2.285 -			all elements without a namespace
   2.286 -
   2.287 -		<dt><span class=css data-link-type=maybe title=*>*</span>
   2.288 -		<dd>
   2.289 -			if no default namespace has been specified,
   2.290 -			this is equivalent to *|*.
   2.291 -			Otherwise it is equivalent to ns|*
   2.292 -			where ns is the default namespace.
   2.293 -	</dl>
   2.294 -
   2.295 -<p>A universal selector containing a namespace prefix
   2.296 -	that has not been previously <a href=#nsdecl>declared</a>
   2.297 -	is an <a data-link-type=dfn href=#invalid-selector title="invalid selector">invalid selector</a>.</p>
   2.298 -
   2.299  
   2.300  <h2 class="heading settled heading" data-level=6 id=attribute-selectors><span class=secno>6 </span><span class=content>
   2.301  Attribute selectors</span><a class=self-link href=#attribute-selectors></a></h2>
   2.302 @@ -3927,7 +3910,7 @@
   2.303  		or should we stick with defaulting to *not* allowing,
   2.304  		and requiring individual pseudo-classes to specify that they work on pseudo-elements?
   2.305  
   2.306 -	<a href=#issue-73b391d2> ↵ </a></div><div class=issue>Explain this better.<a href=#issue-2422b936> ↵ </a></div><div class=issue>Add comma-separated syntax for
   2.307 +	<a href=#issue-73b391d2> ↵ </a></div><div class=issue>Explain this better.<a href=#issue-2422b936> ↵ </a></div><div class=issue>Do we want to extend this protection from default namespaces to other things?<a href=#issue-fdaebe5f> ↵ </a></div><div class=issue>Add comma-separated syntax for
   2.308  	<a href=http://lists.w3.org/Archives/Public/www-style/2011Mar/0215.html>multiple-value matching</a>?
   2.309  	e.g. [rel ~= next, prev, up, first, last]
   2.310