public ProtoXamlInstruction NamespacePrefixDeclaration(string prefix, string ns) { if (PrefixRegistrationMode == PrefixRegistrationMode.Automatic) { var prefixRegistration = new PrefixRegistration(prefix, ns); if (!typeContext.RegisteredPrefixes.Contains(prefixRegistration)) { typeContext.RegisterPrefix(prefixRegistration); } } return(new ProtoXamlInstruction { Namespace = ns, XamlType = null, NodeType = NodeType.PrefixDefinition, Prefix = prefix, }); }