--- a/notes.txt	Sun May 07 22:03:31 2017 +0100
+++ b/notes.txt	Tue May 09 23:08:18 2017 +0100
@@ -102,7 +102,7 @@
  ??? Variables on l or r of ranges are just looked up: if they are complex
   no recursion is done: the _semantics_ of this case are not clear to
   me, need a real-life example... 
- @@ Variables whose value is itself a range are not being handled
+ Variables whose value is itself a range are not being handled FIXED
 -----------
 Switch to default namespace in order to reduce size and improve
 readability, and to elements instead of attributes DONE
@@ -188,5 +188,31 @@
     row ::= abs | rel
     abs ::= '\xAA' xs:positiveInteger
     rel ::= '\xAE' ( ( '-' xs:positiveInteger ) | xs:nonNegativeInteger )
-
-    
+-----------
+Picking colours to label regions, e.g. with similar formulae:
+  http://stackoverflow.com/questions/470690/how-to-automatically-generate-n-distinct-colors
+Start with just top-n, limited to 22 from Kelly
+    #FFB300, # Vivid Yellow
+    #803E75, # Strong Purple
+    #FF6800, # Vivid Orange
+    #A6BDD7, # Very Light Blue
+    #C10020, # Vivid Red
+    #CEA262, # Grayish Yellow
+    #817066, # Medium Gray
+    # The following don't work well for people with defective color vision
+    #007D34, # Vivid Green
+    #F6768E, # Strong Purplish Pink
+    #00538A, # Strong Blue
+    #FF7A5C, # Strong Yellowish Pink
+    #53377A, # Strong Violet
+    #FF8E00, # Vivid Orange Yellow
+    #B32851, # Strong Purplish Red
+    #F4C800, # Vivid Greenish Yellow
+    #7F180D, # Strong Reddish Brown
+    #93AA00, # Vivid Yellowish Green
+    #593315, # Deep Yellowish Brown
+    #F13A13, # Vivid Reddish Orange
+    #232C16, # Dark Olive Green
+------------
+@@ string identify, to say nothing of actual value, is lost -- fix?
+@@ row/column/both spans