[racket] Typed Racket can't filter non-false yet?

From: Sam Tobin-Hochstadt (samth at ccs.neu.edu)
Date: Mon Jan 30 15:37:29 EST 2012

On Mon, Jan 30, 2012 at 3:22 PM, John Clements
<clements at brinckerhoff.org> wrote:
> Am I missing something obvious in either of these?

No.  Typed Racket doesn't have type subtraction, which is what you
need in the first case. I'm not sure why the second case isn't working
right; I think the type of `filter' is a little too restrictive.
sam th
samth at ccs.neu.edu

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