(library (point)
  (export make-point point? point-x point-x-set!)
  (import (chezscheme))

  (define-record-type point
    (fields (mutable x)))

  ;; Usage sites for testing substitution generation
  (define p (make-point 10))
  (define check (point? p))
  (define x-val (point-x p))
  (define set-result (point-x-set! p 20))
)
