[racket] TR Structure Matching

How does one bind an identifier to the matched structure?

In SML, Scala one can do something along the lines of s at S (x y z)

#lang typed/racket

(struct: Thing ())
(struct: Person Thing ([fname : String] [lname : String]))

(: person-name (Person -> String))
(define (person-name p)
  (string-append (Person-lname p) ", " (Person-fname p)))

(define js (Person "Joe" "Smith"))

(: do-it (Thing -> String))
(define (do-it thing)
  (match thing
    ([Person fn ln]
     (displayln fn)
     (person-name thing))))

This fails as `thing' is not recognized as a Person.

I guess I'm wondering if there is something along the lines of the
following in `match'.

(match thing
    (p@[Person fn ln]
     (person-name p)))) ;; p is typed as a Person
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