[r6rs-discuss] port-position and set-port-position!

From: William D Clinger <will>
Date: Tue, 26 Jun 2007 08:08:11 -0400

The 5.95 draft does not mandate any non-custom
textual ports that support set-port-position!.
That is a good thing, and I hope the editors
don't change that at the last minute.

I just noticed two oddities that were introduced
in the 5.93 draft. The first is that the
description of port-position says it "returns an
arbitrary value that is acceptable as input for
set-port-position!". This could be interpreted
as requiring ports that support port-position to
support set-port-position! also, which I hope is
contrary to the editors' intent.

The second is that the specification of
open-string-input-port just says it is
"implementation-dependent" whether the port
supports port-position and set-port-position!,
but the specifications of open-string-output-port
and call-with-string-output-port say the port
"should support the port-position and
set-port-position! operations". Why the
asymmetry?

Will
Received on Tue Jun 26 2007 - 08:08:11 UTC