[racket-dev] [plt] Push #27395: master branch updated

From: Asumu Takikawa (asumu at ccs.neu.edu)
Date: Fri Aug 30 18:30:03 EDT 2013

On 2013-08-30 16:15:23 -0400, Sam Tobin-Hochstadt wrote:
> I worry about mutable sets here, but I can't think of any bugs it can
> cause ATM.

I don't have any segfault-causing bugs, but here's a violation of the blame
theorem:

  #lang racket

  (module a0 racket
    (define s (mutable-set 1 2 3))
    (provide s))

  (module a typed/racket
    (require/typed (submod ".." a0) [s Any])
    (: x (Setof Any))
    (define x (assert s generic-set?))
    (provide x))

  (require 'a)
  x

Cheers,
Asumu

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