[r6rs-discuss] "Unspecified"

From: AndrevanTonder <andre>
Date: Mon Oct 2 13:51:29 2006

On Mon, 2 Oct 2006, Sam TH wrote:

> It is true that `for-each/logging' doesn't work if the procedure
> argument sometimes returns multiple values (or zero values), and thus
> isn't always a drop-in replacement for `for-each'. Many programs that
> take function arguments break in these cases - which was precisely my
> point. We shouldn't make more special cases that have to be coded for,
> when we can allow the standard case to work.

It often has value for an error to be raised, however. I can't say how many
times I have found some mysterious #<void> entries in some data structure
because the "standard case worked" even though it should not have. If zero
values were returned and an inappropriate number of values error had been
raised immediately, such data structures could not even exist. That would be a
powerful gurantee.

Andre
Received on Mon Oct 02 2006 - 13:49:14 UTC