[R6RS] Unspecified question

dyb at cs.indiana.edu dyb at cs.indiana.edu
Thu May 11 23:38:48 EDT 2006


> I'm assuming that the decision to require set! etc. to return the
> unspecified value extends to the cases where the result is unspecified
> in if, case, cond, and do.  If you don't agree, please follow up.
> Otherwise, I'll make the change in a few days.

This was certainly my intent.

Also, although we didn't say so explicitly, I assume that the unspecified
value is unique in the sense of eq?, so that one can use, e.g.,
(eq? x (unspecified)) to determine if x is the unspecified value, and
that the unspecified value is, like the empty list, a special object of
its own type.

Please proceed under these assumptions as well unless someone squawks.

Kent



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