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From: "B. Pym" <Nobody447095@here-nor-there.org>
Newsgroups: comp.lang.lisp
Subject: Re: sequence iteration
Date: Mon, 23 Jun 2025 01:49:35 -0000 (UTC)
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Don Geddis wrote:

> > Is there any generic iteration contruct for sequences?  Ideally it
> > would work just like DOLIST.
> >   > (do-sequence (e "ab c")
> >       (print e))
> >   #\a
> >   #\b
> >   #\Space
> >   #\c
> >   nil
> 
> Well, I don't know if you consider the LOOP macro to be Common Lisp, but
> the following works in Allegro CL 4.2:
> 
>         USER(20): (loop for x across "ab c" do (print x))
> 
>         #\a
>         #\b
>         #\space
>         #\c
>         NIL
> 
> CLtL2 says that the "across" keyword works for iteration over arrays (vectors),
> so it looks to be not quite as generic as over sequences.  But it's close.

Gauche Scheme

(use gauche.collection)

(for-each print '(a b c))
a
b
c

(for-each print #(a b c))
a
b
c

(for-each print "abc")
a
b
c