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From: Andy Wingo <wingo@pobox.com>
To: guile-devel <guile-devel@gnu.org>
Subject: Re: early termination for `map'
Date: Thu, 05 May 2011 20:27:01 +0200	[thread overview]
Message-ID: <m3mxj1vw96.fsf@unquote.localdomain> (raw)
In-Reply-To: <m3zkn1w4pm.fsf@unquote.localdomain> (Andy Wingo's message of "Thu, 05 May 2011 17:24:21 +0200")

On Thu 05 May 2011 17:24, Andy Wingo <wingo@pobox.com> writes:

> If you call `map' or `for-each' with more than one list, our versions of
> these operators will detect if the lists are of unequal length, and
> throw an error in that case.
>
> However, SRFI-1 has long provided an extension to this, to allow for
> early termination when any of the lists runs out.  R6RS adopted this,
> and it looks like R7RS will ratify that.

FWIW I think I misremembered here: R6RS map requires the lists to be of
the same length.

Andy
-- 
http://wingolog.org/



      parent reply	other threads:[~2011-05-05 18:27 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-05 15:24 early termination for `map' Andy Wingo
2011-05-05 15:56 ` Noah Lavine
2011-05-05 16:26 ` Ludovic Courtès
2011-05-05 18:40   ` Andy Wingo
2011-05-05 20:21     ` Ludovic Courtès
2011-05-05 21:12       ` Andy Wingo
2011-05-06 15:41         ` Ludovic Courtès
2011-05-08 15:05         ` ‘map’ and ‘for-each’ written in Scheme Ludovic Courtès
2011-05-08 15:31           ` Andy Wingo
2011-05-05 18:27 ` Andy Wingo [this message]

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