[plt-scheme] Multiple values

From: Jim Blandy (jimb at red-bean.com)
Date: Tue Feb 21 14:26:05 EST 2006

On 2/21/06, Robby Findler <robby at cs.uchicago.edu> wrote:
> They introduce a lot of new errors that were not there before. For
> example, the test position in an if has to check the number of values,
> applications have to check the function and arg positions for the
> number of values, let and letrec have to check their right-hand sides
> for a single value, set! has to check its expression positions is a
> single value ... every non-tail position in the language has to add
> this check.

Wouldn't it make more sense to have a way to recognize continuations
that are prepared to recieve more than one value, and then make code
that returns multiple values responsible for checking that?

(All of this being internal to the implementation, I mean --- I'm not
suggesting any change to the language the user writes in.)


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