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From: "B. Pym" <No_spamming@noWhere_7073.org>
Newsgroups: comp.lang.lisp
Subject: Re: Python syntax in Lisp and Scheme
Date: Sat, 29 Jun 2024 04:25:59 -0000 (UTC)
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Frode Vatvedt Fjeld wrote:

> > Scheme
> > (define vector-fill!
> >   (lambda (v x)
> >     (let ((n (vector-length v)))
> >       (do ((i 0 (+ i 1)))
> >           ((= i n))
> >           (vector-set! v i x)))))
> >
> > Python
> > def vector_fill(v, x):
> >     for i in range(len(v)):
> >         v[i] = x
> >
> > To me the Python code is easier to read, and I can't possibly fathom
> > how somebody could think the Scheme code is easier to read.  It truly
> > boggles my mind. [..]
> 
> The scheme example can only have been written by someone who is on the
> outset determined to demonstrate that sexp-syntax is complicated. This
> is how I'd write it in Common Lisp:
> 
>   (defun vector-fill (v x)
>     (dotimes (i (length v))
>       (setf (aref v i) x)))
> 
> As you can see, it matches the python example quite closely.

Why would any human want to match Python?

;; Racket
(define (vec-fill! v x)
  (vector-map! (const x) v))

;; Gauche Scheme
(define (vec-fill! v x)
  (vector-map! (lambda _ x) v))

(define vec (vector 2 3 4))

(vec-fill! vec 88)

vec
  ===>
#(88 88 88)

However, vector-fill! is already provided.

(vector-fill! vec 99)

vec
  ===>
#(99 99 99)

Multiply each element by 2:

(vector-map! (lambda(n) (* 2 n)) vec)

vec
  ===>
#(198 198 198)