src/Tools/VSCode/src/document_model.scala

--- a/src/Tools/VSCode/src/document_model.scala	Fri Jan 06 23:25:18 2017 +0100
+++ b/src/Tools/VSCode/src/document_model.scala	Sat Jan 07 09:42:57 2017 +0100
@@ -85,6 +85,8 @@
 
   /* edits */
 
+  def is_stable: Boolean = pending_edits.isEmpty
+
   def update_text(text: String): Option[Document_Model] =
   {
     val new_text = Line.normalize(text)