generalized set! in racket - failed idea

set.rkt

#lang racket

(require (for-syntax racket/syntax))

(define toplevel 'foo)

(define-syntax (set^ stx)
  (syntax-case stx ()
    [(_ (attr x) y)
     (with-syntax ([set-attr! (format-id #'toplevel "set-~a!" (syntax-e #'attr))])
       #'(set-attr! x y))]))

(define set-unbox! set-box!)

(define (t1)
  (let ((b (box 3)))
    (set^ (unbox b) 5)
    (unbox b)))

; > (t1)
; 5

(define (t2)
  (let ((b (box 3)))
    (let ((set-unbox! 'blah))
      (set^ (unbox b) 5)
      (unbox b))))

;> (t2)
; 5



or even just use a function

(set! 'car thing value)