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From: lpl@cunixb.cc.columbia.edu (Leonard P Lidov)
Newsgroups: comp.lang.scheme
Subject: Re: news
Message-ID: <1991Mar2.000059.16156@cunixf.cc.columbia.edu>
Date: 2 Mar 91 00:00:59 GMT
References: <1991Mar1.153624.45733@vaxb.acs.unt.edu>
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Reply-To: lpl@cunixb.cc.columbia.edu (Leonard P Lidov)
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In article <1991Mar1.153624.45733@vaxb.acs.unt.edu> munawar@vaxb.acs.unt.edu writes:

>  My problem is to flatten
>  '((a b)(c d)(e f)) in to '(a b c d e f)
>I am not sure how to tackle this problem specifically in _TI PCSCHEME_
>

Gee--do you need a PCScheme specific solution?? The problem isn't hard, 
though: 

using a nicely abstracted form from Ableson & Susman:

given that z is ((a b) (c d) (e f)):

(define (accumulate combiner init-value l)
	(if (null? l)
	    init-value
	    (combiner (car l) (accumulate combiner init-value (cdr l)))))

(accumulate append '() z)

ought to produce (a b c d e f) pretty easily.

Good Luck,

Len

"All history is the history of CS"
			Marx