[racket-dev] Class contracts: opaque or transparent?

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Fri Apr 27 17:44:06 EDT 2012

On Apr 27, 2012, at 1:48 PM, Asumu Takikawa wrote:

>  * Composability: opaque class contracts are not composable since each
>    one requires the entire specification. This shouldn't be a problem
>    since the individual class/c clauses can be composed/reused (e.g., ->m
>    contracts).

[[If you mentioned this issue in my office yesterday, I failed to catch it.]]

In the old world, I could write contracts such as 

 (and/c (class/cc ...) (class/c ...))

and that was *really convenient*. Are you saying I can
no longer do so? 

-- Matthias

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