[racket-dev] [plt] Push #24906: master branch updated

From: Asumu Takikawa (asumu at ccs.neu.edu)
Date: Mon Jun 25 22:27:24 EDT 2012

On 2012-06-25 21:19:33 -0500, Robby Findler wrote:
> What do you mean by "made opaque by key/c"?

The prototype I wrote would bind the parameters provided in the
`#:params` argument to contracts produced by `new-∀/c`. If `key/c` is
one of the parameters, then `dict-ref` with a key argument wraps it in
an opaque struct.

The constructor isn't part of the interface (and can't be in the current
implementation of `define-generics`), so the initial keys in the
dictionaries aren't wrapped in opaque structs, causing lookups of the
initial keys to fail.

Cheers,
Asumu

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