// Copy-modify the input properties to expect a partial element that
// wraps the expected type
ElementMetadata<?, ?> metadata = inProps.getRootMetadata();
InputProperties partialProperties =
new InputPropertiesBuilder(inProps)
.setElementMetadata(new PartialMetadata(metadata))
.build();
// Create a parser to parse the partial-wrapped representation
InputParser<Partial> partialParser = new PartialParser(fullParser);
Partial p =