made sure map() doesn't mutate internal list linked-ness

HISTORY.md

@@ -24,6 +24,7 @@
 * blocks: made pen attributes menus static
 * blocks: made sensing attributes menus largely static
 * threads: changed reportVideo() to be hyper-monadic
+* lists: made sure map() doesn't mutate internal list linked-ness
 
 ### 2020-11-30
 * threads: keep internal linked-list organization intact for hyperblocks

snap.html

@@ -13,7 +13,7 @@
         <script src="src/objects.js?version=2020-12-01"></script>
         <script src="src/gui.js?version=2020-12-01"></script>
         <script src="src/paint.js?version=2020-05-17"></script>
-        <script src="src/lists.js?version=2020-07-01"></script>
+        <script src="src/lists.js?version=2020-12-01"></script>
         <script src="src/byob.js?version=2020-11-27"></script>
         <script src="src/tables.js?version=2020-10-06"></script>
         <script src="src/sketch.js?version=2020-07-13"></script>

src/lists.js

@@ -63,7 +63,7 @@ MorphicPreferences, TableDialogMorph, SpriteBubbleMorph, SpeechBubbleMorph,
 TableFrameMorph, TableMorph, Variable, isSnapObject, Costume, contains, detect,
 ZERO, WHITE*/
 
-modules.lists = '2020-July-01';
+modules.lists = '2020-December-01';
 
 var List;
 var ListWatcherMorph;
@@ -211,7 +211,7 @@ List.prototype.clear = function () {
 
 List.prototype.map = function(callback) {
     return new List(
-        this.asArray().map(callback)
+        this.itemsArray().map(callback)
     );
 };