[racket] problem with map example in docs of typed/racket

From: Sam Tobin-Hochstadt (samth at ccs.neu.edu)
Date: Thu Aug 26 16:18:09 EDT 2010

On Thu, Aug 26, 2010 at 3:54 PM, Jos Koot <jos.koot at telefonica.net> wrote:
> Two things worry me:
> In your version,
> (my-map list '(1 2 3) '(a b c))
> results in an exception.

That's because TR cannot infer the type instantiation for `list' when
it's used as an argument.

> 2:
> Replacing the internal calls to map by calls to my-map does not pass
> check-syntax.

Yes, `map' (the built-in one) has special handling in the presence of
... types.  We've worked on reducing the amount of special casing, but
it's not all gone yet.
sam th
samth at ccs.neu.edu

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