super(MuleOrphanDefinitionParser.ROOT_ELEMENT, new ExpressionTransformerOrphanDefinitionParser(
messageProcessor, false));
otherwise(new ExpressionTransformerChildDefinitionParser("messageProcessor", messageProcessor));
registerPreProcessor(
new CheckRequiredAttributesWhenNoChildren(new String[][]{{"evaluator", "expression"}},
"return-argument")).registerPreProcessor(
new CheckExclusiveAttributesAndChildren(new String[]{"evaluator", "expression"},
new String[]{"return-argument"}))
.addIgnored("evaluator")
.addIgnored("expression")