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Date: Tue, 31 Jan 89 13:46:07 PDT
From: William Clinger <email@example.com>
I am uncomfortable with the proposed WITH-INPUT-FROM-PORT and
WITH-OUTPUT-TO-PORT procedures. One reason the R3RS did not specify a
way to change the default ports is that some people do not want them to
be changable. Furthermore the implementation-dependent behavior of
these new procedures is a serious problem because they muck with a
global resource: the default ports....
Date: Tue, 31 Jan 89 20:51:41 EST
From: firstname.lastname@example.org (Chris Hanson)
This shouldn't be an issue. The procedures `with-input-from-file' and
`with-output-to-file' already do this kind of binding. What we're
suggesting isn't new functionality, but a subset of existing
functionality: we want the binding part of `with-...-file' separately
from the file-opening part.
Right. I was confused. But now that I'm not, I'm more concerned than
before. WITH-INPUT-FROM-FILE and WITH-OUTPUT-TO-FILE are not essential,
precisely because they are not well-defined. Historically, their presence
in R3RS at all was a grudging concession to MIT Scheme. On the other hand,
CALL-WITH-INPUT-FILE and CALL-WITH-OUTPUT-FILE are well-defined and essential.
I do not see why IEEE Scheme should drop well-defined, essential procedures in
favor of ill-defined procedures that don't even appear in R3RS, even if the
new procedures resemble two non-essential and ill-defined R3RS procedures.