From: Andy Wingo <wingo@pobox.com>
To: ludo@gnu.org (Ludovic Courtès)
Cc: guile-devel@gnu.org
Subject: Re: read-all ?
Date: Tue, 22 Jan 2013 12:04:51 +0100 [thread overview]
Message-ID: <87liblwka4.fsf@pobox.com> (raw)
In-Reply-To: <8738xtk03k.fsf@gnu.org> ("Ludovic Courtès"'s message of "Tue, 22 Jan 2013 11:01:35 +0100")
On Tue 22 Jan 2013 11:01, ludo@gnu.org (Ludovic Courtès) writes:
>>> Are the names right?
>
> ‘read-all’ doesn’t convey the idea that it’s textual (unlike the R6RS
> names).
>
> Perhaps ‘port-contents-as-string’, or ‘read-all-string’, or...?
What about read-string with an optional #:count argument ?
>> + (let lp ((n start))
>> + (if (< n end)
>> + (let ((c (read-char port)))
>> + (if (eof-object? c)
>> + (- n start)
>> + (begin
>> + (string-set! buf n c)
>> + (lp (1+ n)))))
>> + (- n start))))
>
> As you note, this is fairly inefficient, like ‘get-string-n!’.
It is exactly what %read-delimited does, though, and that's the most
efficient thing we have. read-string/partial! does something more
clever, but I don't understand it fully. I was thinking (ice-9 ports)
could be appropriate if we exposed port buffers to scheme, because that
way we could read characters in bulk. Dunno.
> Given that ‘string-set!’ is (unduly) costly, I wonder if consing all the
> chars and then calling ‘list->string’ wouldn’t be more efficient in time
> (it’d be less efficient in space.)
Probably not, I would say that the interface is more important than the
implementation.
So, proposal: read-all{,!} to read-string{,!} and add optional count
argument to read-string, and leave it in ice-9 rdelim. WDYT?
Andy
--
http://wingolog.org/
next prev parent reply other threads:[~2013-01-22 11:04 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-12 17:34 read-all ? Andy Wingo
2013-01-12 21:22 ` Ludovic Courtès
2013-01-22 9:15 ` Andy Wingo
2013-01-22 9:51 ` Andy Wingo
2013-01-22 10:01 ` Ludovic Courtès
2013-01-22 11:04 ` Andy Wingo [this message]
2013-01-22 13:32 ` Ludovic Courtès
2013-01-22 15:16 ` Andy Wingo
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