Is it possible to use Generic Named Types (decorators)?

Is it possible to use Generic Named Types as described here: https://github.com/apiaryio/mson/blob/master/MSON%20Specification.md

and here:
https://apiblueprint.org/documentation/mson/specification.html#53-generic-named-type

example:

# Address Decorator (*T*)
- address

# Person (object)
- `first_name`
- `last_name`

Use as:

- `decorated_person` (Address Decorator(Person))

Implies the same structure as:

- decorated_person (object)
- `first_name`
- `last_name`
- address

When I use it in my document, aglio throws the following error:

message: 'Error parsing input: base type \'Address Decorator(Person)\' is not defined in the document'