added dataset attr removal...

Signed-off-by: Alex A. Naanou <alex.nanou@gmail.com>

experiments/outline-editor/editor.js

@@ -1570,6 +1570,8 @@ var Outline = {
 
 	// NOTE: this does not internally handle undo as it would be too 
 	// 		granular...
+	// NOTE: to remove an attribute set it's value to null, undefined, 
+	// 		'null', or 'undefined'
 	update: function(node='focused', data){
 		var node = this.get(node)
 		data ??= this.data(node, false)
@@ -1615,7 +1617,9 @@ var Outline = {
 					: node.removeAttribute(attr) 
 			// dataset...
 			} else {
-				if(value == null){
+				if(value == null
+						|| value == 'null'
+						|| value == 'undefined'){
 					delete node.dataset[attr]
 				} else {
 					node.dataset[attr] = value } } }

experiments/outline-editor/index.html

@@ -143,15 +143,9 @@ var setup = function(){
         |text|text|text|
   -
 - ## ToDo:
-  - attributes: `.data(..)`: read in element attributes...
-    - would be logical to store system attrs (`.__block_attrs__`) as attrs while the rest as data-attrs - this would bot simplify retrieval and avoid shadowing html attrs...
-    - TEST: this item has attr `moo` with value `"foo"`
-      moo::foo
-    - need a way to remove attributes from editor -- `null` or `undefined` special values??
   - attributes: need to show/hide the attributes -- option?
   - TOC: Q: should we have both manual and auto headings???
     - IMHO: no...
-  - DONE TOC: headings that do not show up in toc -- `# ...` shows up while `@ ...` does not...
   - TOC: tweaking: add args like depth, ... -- as attributes...
   - ASAP: expand sub-tree on follow link...
   - export auto-headings as normal/manual markdown headings...
@@ -273,6 +267,12 @@ var setup = function(){
       - `<editable/>` -- field marker
       - each child node will copy the template and allow editing of only fields
       - not clear how to handle template changes...
+  - DONE attributes: need a way to remove attributes from editor -- `null` or `undefined` special values??
+  - DONE attributes: `.data(..)`: read in element attributes...
+    collapsed:: true
+    - TEST: this item has attr `moo` with value `"foo"`
+      moo::foo
+  - DONE TOC: headings that do not show up in toc -- `# ...` shows up while `@ ...` does not...
   - DONE \TOC global/local
   - DONE FEATURE dynamic headings -- level depends on number of headings above...
     - DONE Experimental syntax: