lib/rubyXL/objects/worksheet.rb in rubyXL-3.3.12 vs lib/rubyXL/objects/worksheet.rb in rubyXL-3.3.13

@@ -671,10 +671,10 @@
     define_child_node(RubyXL::WebPublishingItems)
     define_child_node(RubyXL::TableParts)
     define_child_node(RubyXL::ExtensionStorageArea)
     define_child_node(RubyXL::AlternateContent)
     define_element_name 'worksheet'
-    set_namespaces('http://schemas.openxmlformats.org/spreadsheetml/2006/main' => '',
+    set_namespaces('http://schemas.openxmlformats.org/spreadsheetml/2006/main' => nil,
                    'http://schemas.openxmlformats.org/officeDocument/2006/relationships' => 'r',
                    'http://schemas.openxmlformats.org/markup-compatibility/2006' => 'mc',
                    'http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac' => 'x14ac',
                    'urn:schemas-microsoft-com:mac:vml' => 'mv')