some additions to pR 1794:

add a special XMLAttributeError class to indicate an error when accessing a missing attribute
in PropertyContainer::Restore make error handling more flexible

src/Base/Reader.cpp

@@ -175,8 +175,8 @@ const char*  Base::XMLReader::getAttribute (const char* AttrName) const
     else {
         // wrong name, use hasAttribute if not sure!
         std::ostringstream msg;
-        msg << "Attribute: \"" << AttrName << "\" not found";
-        THROWM(Base::AttributeError, msg.str());
+        msg << "XML Attribute: \"" << AttrName << "\" not found";
+        throw Base::XMLAttributeError(msg.str());
     }
 }