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Re: specification of STREAM-UNFOLDN generators

This page is part of the web mail archives of SRFI 40 from before July 7th, 2015. The new archives for SRFI 40 contain all messages, not just those from before July 7th, 2015.



Michael Sperber <sperber@xxxxxxxxxxxxxxxxxxxxxxxxxxx> writes:

> >>>>> "Matze" == Matthias Neubauer <neubauer@xxxxxxxxxxxxxxxxxxxxxxxxxx> writes:
> 
> Matze> Additionally, #f feels more like signaling "the end" to me
> Matze> ... :-)
> 
> More so than '(), the literal for what's officially called the "empty
> list"?

Yeah, definitely!

Note that the result we are returning here is *not* the result stream
per se; it rather specifies the *new elements* that we want to prepend
to the result stream.

So, this case is more like a typical error case, saying something like
"Dude, you have to stop prepending to the result stream ..."

I always thought cases like this are typically signaled by #f in
Scheme, aren't they?

-Matthias

-- 
Matthias Neubauer                                       |
Universität Freiburg, Institut für Informatik           | tel +49 761 203 8060
Georges-Köhler-Allee 79, 79110 Freiburg i. Br., Germany | fax +49 761 203 8052