Change display of "empty" types.untyped.Set object (Issue #561) (#616)

* Overload isempty method for types.untyped.Set (Issue #561)

* Remove dead code

* Update display of empty object

Author: ehennestad

+io/parseGroup.m

@@ -55,12 +55,6 @@
 if isempty(Type.typename)
     parsed = types.untyped.Set(...
         [attributeProperties; datasetProperties; groupProperties; linkProperties]);
-    
-    if isempty(parsed)
-        %special case where a directory is simply empty.  Return itself but
-        %empty
-        parsed(root) = [];
-    end
 else
     if groupProperties.Count > 0
         %elide group properties

+types/+untyped/Set.m

@@ -70,7 +70,7 @@
         function cnt = Count(obj)
             cnt = obj.Map.Count;
         end
-        
+
         %overloads size(obj)
         function varargout = size(obj, dim)
             if nargin > 1
@@ -80,7 +80,7 @@
                     varargout{1} = obj.Count;
                 end
             else
-                if nargout == 1
+                if nargout == 0 || nargout == 1
                     varargout{1} = [obj.Count, 1];
                 else
                     varargout = num2cell( ones(1, nargout) );
@@ -193,9 +193,9 @@ function validateAll(obj)
 
     methods(Access=protected)
         function displayEmptyObject(obj)
-            hdr = ['  Empty '...
-                '<a href="matlab:helpPopup types.untyped.Set" style="font-weight:bold">'...
-                'Set</a>'];
+            hdr = sprintf('  %s with no elements.', ...
+                ['<a href="matlab:helpPopup types.untyped.Set" style="font-weight:bold">'...
+                'Set</a>']);
             footer = getFooter(obj);
             disp([hdr newline footer]);
         end