 
 (defun fstar--beginning-of-sexp (pos)
   "Find beginning of sexp enclosing POS."
-  (or (nth 1 (syntax-ppss pos)) 1))
+  (or (nth 1 (fstar--syntax-ppss pos)) 1))
 
 (defun fstar-subexpr-pre-matcher (rewind-to &optional bound-to)
   "Move past REWIND-TO th group, then return end of BOUND-TO th.

    (setq prompt (format prompt default-info)))
  (read-string prompt nil nil default))

(defun fstar-in-comment-p (&optional pos)
  "Return non-nil if POS is inside a comment."
  (nth 4 (syntax-ppss pos)))

(defun fstar--column-in-commment-p (column)
  "Return non-nil if point at COLUMN is inside a comment."

        (opener-2 (string-to-syntax ". 2")))
    (syntax-propertize-rules
     ("//" (0 (let* ((pt (match-beginning 0))
                     (state (fstar--syntax-ppss pt)))
                (unless (or (nth 3 state) (nth 4 state))
                  (put-text-property pt (+ pt 1) 'syntax-table opener-1)
                  (put-text-property (+ pt 1) (+ pt 2) 'syntax-table opener-2)
