[racket-dev] typed/racket for loops?

I can't get typed racket to work with for loops, e.g.:

#lang typed/racket

(: p (Listof Natural))
(define p 
  (for/list: : Natural ([i (in-range 30)]) i))

==> Type Checker: Error in macro expansion -- untyped variable: for-loop in: (for/list: : Natural ((i (in-range 30))) i)


Am I doing something silly here? I tried annotating the type of the loop variable 'i', with no change in the error message.

John

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