Editorial: Add Iterator Record type (#2591)

Co-authored-by: ExE Boss <ExE-Boss@code.ExE-Boss.tech>
Co-authored-by: Michael Dyck <jmdyck@ibiblio.org>

Author: 2 people

spec.html

@@ -6909,12 +6909,66 @@ <h1>
     <h1>Operations on Iterator Objects</h1>
     <p>See Common Iteration Interfaces (<emu-xref href="#sec-iteration"></emu-xref>).</p>
 
+    <emu-clause id="sec-iterator-records">
+      <h1>Iterator Records</h1>
+      <p>An <dfn variants="Iterator Records">Iterator Record</dfn> is a Record value used to encapsulate an Iterator or AsyncIterator along with the `next` method.</p>
+      <p>Iterator Records have the fields listed in <emu-xref href="#table-iterator-record-fields"></emu-xref>.</p>
+      <emu-table id="table-iterator-record-fields" caption="Iterator Record Fields">
+        <table>
+          <tr>
+            <th>
+              Field Name
+            </th>
+            <th>
+              Value
+            </th>
+            <th>
+              Meaning
+            </th>
+          </tr>
+          <tr>
+            <td>
+              [[Iterator]]
+            </td>
+            <td>
+              An object
+            </td>
+            <td>
+              An object that conforms to the <i>Iterator</i> or <i>AsyncIterator</i> interface.
+            </td>
+          </tr>
+          <tr>
+            <td>
+              [[NextMethod]]
+            </td>
+            <td>
+              A function object
+            </td>
+            <td>
+              The `next` method of the [[Iterator]] object.
+            </td>
+          </tr>
+          <tr>
+            <td>
+              [[Done]]
+            </td>
+            <td>
+              Boolean
+            </td>
+            <td>
+              Whether the iterator has been closed.
+            </td>
+          </tr>
+        </table>
+      </emu-table>
+    </emu-clause>
+
     <emu-clause id="sec-getiterator" type="abstract operation">
       <h1>
         GetIterator (
-          _obj_: unknown,
+          _obj_: an ECMAScript language value,
           optional _hint_: ~sync~ or ~async~,
-          optional _method_: unknown,
+          optional _method_: a function object,
         )
       </h1>
       <dl class="header">
@@ -6932,16 +6986,16 @@ <h1>
         1. Let _iterator_ be ? Call(_method_, _obj_).
         1. If Type(_iterator_) is not Object, throw a *TypeError* exception.
         1. Let _nextMethod_ be ? GetV(_iterator_, *"next"*).
-        1. Let _iteratorRecord_ be the Record { [[Iterator]]: _iterator_, [[NextMethod]]: _nextMethod_, [[Done]]: *false* }.
+        1. Let _iteratorRecord_ be the Iterator Record { [[Iterator]]: _iterator_, [[NextMethod]]: _nextMethod_, [[Done]]: *false* }.
         1. Return _iteratorRecord_.
       </emu-alg>
     </emu-clause>
 
     <emu-clause id="sec-iteratornext" type="abstract operation">
       <h1>
         IteratorNext (
-          _iteratorRecord_: unknown,
-          optional _value_: unknown,
+          _iteratorRecord_: an Iterator Record,
+          optional _value_: an ECMAScript language value,
         )
       </h1>
       <dl class="header">
@@ -6985,7 +7039,7 @@ <h1>
     <emu-clause id="sec-iteratorstep" type="abstract operation">
       <h1>
         IteratorStep (
-          _iteratorRecord_: unknown,
+          _iteratorRecord_: an Iterator Record,
         )
       </h1>
       <dl class="header">
@@ -7003,7 +7057,7 @@ <h1>
     <emu-clause id="sec-iteratorclose" type="abstract operation">
       <h1>
         IteratorClose (
-          _iteratorRecord_: unknown,
+          _iteratorRecord_: an Iterator Record,
           _completion_: a Completion Record,
         )
       </h1>
@@ -7042,7 +7096,7 @@ <h1>IfAbruptCloseIterator ( _value_, _iteratorRecord_ )</h1>
     <emu-clause id="sec-asynciteratorclose" type="abstract operation">
       <h1>
         AsyncIteratorClose (
-          _iteratorRecord_: unknown,
+          _iteratorRecord_: an Iterator Record,
           _completion_: a Completion Record,
         )
       </h1>
@@ -7069,7 +7123,7 @@ <h1>
     <emu-clause id="sec-createiterresultobject" type="abstract operation">
       <h1>
         CreateIterResultObject (
-          _value_: unknown,
+          _value_: an ECMAScript language value,
           _done_: a Boolean,
         )
       </h1>
@@ -7088,7 +7142,7 @@ <h1>
     <emu-clause id="sec-createlistiteratorRecord" type="abstract operation" oldids="sec-createlistiterator,sec-listiteratornext-functions,sec-listiterator-next">
       <h1>
         CreateListIteratorRecord (
-          _list_: unknown,
+          _list_: a List,
         )
       </h1>
       <dl class="header">
@@ -7101,7 +7155,7 @@ <h1>
             1. Perform ? GeneratorYield(! CreateIterResultObject(_E_, *false*)).
           1. Return *undefined*.
         1. Let _iterator_ be ! CreateIteratorFromClosure(_closure_, ~empty~, %IteratorPrototype%).
-        1. Return Record { [[Iterator]]: _iterator_, [[NextMethod]]: %GeneratorFunction.prototype.prototype.next%, [[Done]]: *false* }.
+        1. Return the Iterator Record { [[Iterator]]: _iterator_, [[NextMethod]]: %GeneratorFunction.prototype.prototype.next%, [[Done]]: *false* }.
       </emu-alg>
       <emu-note>
         <p>The list iterator object is never directly accessible to ECMAScript code.</p>
@@ -7111,8 +7165,8 @@ <h1>
     <emu-clause id="sec-iterabletolist" type="abstract operation">
       <h1>
         IterableToList (
-          _items_: unknown,
-          optional _method_: unknown,
+          _items_: an ECMAScript language value,
+          optional _method_: a function object,
         )
       </h1>
       <dl class="header">
@@ -21958,7 +22012,7 @@ <h1>
             1. Let _obj_ be ! ToObject(_exprValue_).
             1. Let _iterator_ be ? EnumerateObjectProperties(_obj_).
             1. Let _nextMethod_ be ! GetV(_iterator_, *"next"*).
-            1. Return the Record { [[Iterator]]: _iterator_, [[NextMethod]]: _nextMethod_, [[Done]]: *false* }.
+            1. Return the Iterator Record { [[Iterator]]: _iterator_, [[NextMethod]]: _nextMethod_, [[Done]]: *false* }.
           1. Else,
             1. Assert: _iterationKind_ is ~iterate~ or ~async-iterate~.
             1. If _iterationKind_ is ~async-iterate~, let _iteratorHint_ be ~async~.
@@ -42876,13 +42930,13 @@ <h1>
         </h1>
         <dl class="header">
           <dt>description</dt>
-          <dd>It is used to create an async iterator Record from a synchronous iterator Record.</dd>
+          <dd>It is used to create an async Iterator Record from a synchronous Iterator Record.</dd>
         </dl>
         <emu-alg>
           1. Let _asyncIterator_ be ! OrdinaryObjectCreate(%AsyncFromSyncIteratorPrototype%, &laquo; [[SyncIteratorRecord]] &raquo;).
           1. Set _asyncIterator_.[[SyncIteratorRecord]] to _syncIteratorRecord_.
           1. Let _nextMethod_ be ! Get(_asyncIterator_, *"next"*).
-          1. Let _iteratorRecord_ be the Record { [[Iterator]]: _asyncIterator_, [[NextMethod]]: _nextMethod_, [[Done]]: *false* }.
+          1. Let _iteratorRecord_ be the Iterator Record { [[Iterator]]: _asyncIterator_, [[NextMethod]]: _nextMethod_, [[Done]]: *false* }.
           1. Return _iteratorRecord_.
         </emu-alg>
       </emu-clause>
@@ -42986,7 +43040,7 @@ <h1>Properties of Async-from-Sync Iterator Instances</h1>
                 [[SyncIteratorRecord]]
               </td>
               <td>
-                A Record, of the type returned by GetIterator, representing the original synchronous iterator which is being adapted.
+                An Iterator Record representing the original synchronous iterator which is being adapted.
               </td>
             </tr>
           </table>