removeCache: refactor Sources Mixin

Author: mpsonntag

+nix/SourcesMixIn.m

@@ -12,15 +12,13 @@
         end
 
         function [] = add_source(obj, add_this)
-            obj.sourcesCache = nix.Utils.add_entity(obj, ...
-                add_this, 'nix.Source', ...
-                strcat(obj.alias, '::addSource'), obj.sourcesCache);
+            nix.Utils.add_entity_(obj, add_this, ...
+                'nix.Source', strcat(obj.alias, '::addSource'));
         end;
 
         function delCheck = remove_source(obj, del)
-            [delCheck, obj.sourcesCache] = nix.Utils.delete_entity(obj, ...
-                del, 'nix.Source', strcat(obj.alias, '::removeSource'), ...
-                obj.sourcesCache);
+            delCheck = nix.Utils.delete_entity_(obj, del, ...
+                'nix.Source', strcat(obj.alias, '::removeSource'));
         end;
 
         function retObj = open_source(obj, id_or_name)
@@ -31,4 +29,3 @@
     end
 
 end
-