[css-pseudo-4] Switch pseudo() to return instance rather than list. Delete list interface since now nothing uses it? #3541 (comment)

Author: fantasai

css-pseudo-4/Overview.bs

@@ -891,57 +891,25 @@ Interface CSSPseudoElement</h3>
   must be implemented by all instances of <code>CSSPseudoElement</code>
   as a conformance requirement of this module.
 
-<h3 id="CSSPseudoElementList-interface">
-Interface CSSPseudoElementList</h3>
-
-  The <code>CSSPseudoElementList</code> represents an ordered collection
-  of <code>CSSPseudoElement</code> instances.
-
-  <pre class="idl">
-    [Exposed=Window]
-    interface CSSPseudoElementList {
-        readonly attribute unsigned long <a href="#dom-csspseudochildlist-length">length</a>;
-        CSSPseudoElement <a href="#dom-csspseudochildlist-item">item</a>(unsigned long index);
-        CSSPseudoElement <a href="#dom-csspseudochildlist-getbytype">getByType</a>(CSSOMString type);
-                         // replies null if no pseudo-element exists for
-                         //     the requested type
-    };
-  </pre>
-
-  The <dfn id="dom-csspseudochildlist-length">length</dfn> attribute
-  represents the number of <code>CSSPseudoElement</code> in the
-  collection or zero if it is empty.
-  The method <dfn id="dom-csspseudochildlist-item">item()</dfn>
-  is used to retrieve a <code>CSSPseudo</code><code>Element</code> by index.
-  It takes one parameter being the requested index into the collection.
-  Its return value is the <code>CSSPseudo</code><code>Element</code>
-  at the requested index in the collection
-  or null if that is not a valid index.
-
-  The method <dfn id="dom-csspseudochildlist-getbytype">getByType()</dfn>
-  is used to retrieve a <code>CSSPseudo</code><code>Element</code>
-  by its type.
-  Its return value is the <code>CSSPseudo</code><code>Element</code>
-  in the collection that matches the type
-  or null if there is no <code>CSSPseudo</code><code>Element</code>
-  in the collection for that type.
-
 <h3 id="window-interface">
 Addition to the <code>Element</code> interface</h3>
 
   A new method is added to the <code>Element</code> interface to retrieve
   pseudo-elements created by a given element for a given type:
   <pre class="idl">
     partial interface Element {
-      CSSPseudoElementList <a href="#dom-window-getpseudochildren">pseudo</a>(CSSOMString type);
+      CSSPseudoElement? <a href="#dom-element-pseudo">pseudo</a>(CSSOMString type);
     };
   </pre>
 
   The <dfn id="dom-element-pseudo"><code>pseudo()</code></dfn> method
-  is used to retrieve all <code>CSSPseudoElement</code> instances
-  created by the element <code>elt</code> for the type <code>type</code>.
-  Its return value is a <code>CSSPseudoElementList</code>,
-  potentially empty if no pseudo-element exists for the given element and the given type.
+  is used to retrieve the <code>CSSPseudoElement</code> instance
+  created by the element of the type matching <code>type</code>.
+  Its return value is a <code>CSSPseudoElement</code>,
+  potentially null if no such pseudo-element exists.
+
+  Pseudo-elements of unsupported types are considered to simply not exist;
+  unrecognized <code>type</code> values are not an error.
 
 <h2 id="css2-compat">
 Compatibilitiy Syntax</h2>