Current line number in PLT Scheme

Here is how to get the current line number programmatically in PLT Scheme (via Jay):

#lang scheme
(define-syntax (current-line-number stx)
  (quasisyntax/loc stx
    '#,(syntax-line stx)))
(printf "~a: ~a~n" (current-line-number) 6)
(printf "~a: ~a~n" (current-line-number) 8)

(via plt)