[plt-scheme] Typed scheme and varying arity

From: Sam Tobin-Hochstadt (samth at ccs.neu.edu)
Date: Fri Apr 30 13:46:43 EDT 2010

On Fri, Apr 30, 2010 at 12:35 PM, Sam Phillips <samdphillips at gmail.com> wrote:

> ... but I can't seem to get the function signature correct for
> the varying case.
> (: foo
>  (All (a b ...)
>    ((Boxof a) (Boxof b) ... b -> (Boxof (List b ... b)))))
> Type Checker: Type variable b must be used with ... in: b

Right now, `typed/scheme' doesn't support signatures like the one
you've written here.  ... can only appear at the end of function
argument lists, and inside (Values -).  However, we're right now
working on extending the system to handle just these kind of cases.  I
hope that Stevie and I will have something to announce this summer.
sam th
samth at ccs.neu.edu

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