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From: "B. Pym" <Nobody447095@here-nor-there.org>
Newsgroups: comp.lang.lisp,comp.lang.scheme
Subject: re: Elegant solution asked
Date: Sat, 7 Sep 2024 08:19:39 -0000 (UTC)
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> > Very often I need a function to map a 2 argument function over a list and
> > a fixed argument. For example, if we call such function map1:
> > (map1 #'list 'z '(a b c)) should return: '((z a) (z b) (z c))
> >
> > Can anyone suggest an elegant solution for this. The best I could come up
> > with was:
> >
> > (defun map1 (function fixed-argument list)
> >     (mapcar (lambda (element) (funcall fn fixed-argument element)) list))
> >
> > This works fine, but I have the gut feeling that there must be a
> > better/simpler way. Any ideas?
> > Thanks in advance.
> > Please reply to: lsarasua@epo.e-mail.com
> 
> I prefer the following (I guess because it avoids the funcall), although
> I don't claim it is is significantly better.
> 
> (defun map1 (function fixed_argument list) (mapcar function
>              (mapcar #'(lambda (x) fixed-argument) list) list))

Scheme

(map (curry list '--) '(a b c))
  ===>
((-- a) (-- b) (-- c))

(map (curryr list '--) '(a b c))
  ===>
((a --) (b --) (c --))