blocks|key|2732904|text|查找iota+(如SRFI-1中所定义)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|2732905|示例：(iota+10+1)给出从1开始的10个连续整数(而不是默认值0)。|2732906|iota不接受与range相同的参数，但它复制了所有的功能-升序范围，降序范围，如果只给出一个界限，则从0开始，并能够指定间隔。|2732907|entityMap^0|2|4|0|0|0|4|0^^$0|@$1|2|3|4|5|6|7|L|8|@$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|P|8|@$9|Q|A|R|B|C]]|D|@]|E|$]]|$1|J|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|K|$]]

Look for iota (as defined in SRFI-1).

Example: (iota 10 1) gives 10 consecutive integers starting from 1 (instead of the default of 0).

iota doesn't take the same arguments as range but it duplicates all the functionality - ascending ranges, descending ranges, starting from 0 if only one bound is given, ability to specify the interval.

blocks|key|46786|text|这是一个版本，如果第一个数字较小，则执行升序范围；如果第一个数字较高，则执行降序范围：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|46787|(define+range
++(lambda+(n+m)
++++(cond
++++++((=+n+m)+(list+n))
++++++++(else+(cons+n+(range+((if+(<+n+m)+%2B+-)+n+1)+m))))))|code-block|syntax|javascript|46788|这里有一个改进的版本，它可以接受1到2个参数；如果只给出一个参数，它的范围是从0到给定的数字：|46789|(define+range
++(lambda+(n+.+m)
++++(let
++++++((n+(if+(null?+m)+0+n))+(m+(if+(null?+m)+n+(car+m))))
++++++(cond
++++((=+n+m)+(list+n))
++++(else+(cons+n+(range+((if+(<+n+m)+%2B+-)+n+1)+m)))))))|46790|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Here's a version which does an ascending range if the first number is lower or a descending range if it is higher:

<pre><code>(define range
 (lambda (n m)
 (cond
 ((= n m) (list n))
 (else (cons n (range ((if (&lt; n m) + -) n 1) m))))))
</code></pre>

And here's an improved version which can take 1 or 2 arguments; if only one is given, it does a range from 0 to the given number:

<pre><code>(define range
 (lambda (n . m)
 (let
 ((n (if (null? m) 0 n)) (m (if (null? m) n (car m))))
 (cond
 ((= n m) (list n))
 (else (cons n (range ((if (&lt; n m) + -) n 1) m)))))))
</code></pre>

blocks|key|46816|text|在球拍中有一个内置的range函数，它的行为类似于Python。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|46817|>+(range+10)
'(0+1+2+3+4+5+6+7+8+9)|code-block|syntax|javascript|46818|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.racket-lang.org/reference/pairs.html#%2528def._%2528%2528lib._racket/list..rkt%2529._range%2529%2529^0|A|5|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

There is a built-in <a href="http://docs.racket-lang.org/reference/pairs.html#%28def._%28%28lib._racket/list..rkt%29._range%29%29" rel="noreferrer">range</a> function in Racket that behaves like that of Python.

<pre><code>&gt; (range 10)
'(0 1 2 3 4 5 6 7 8 9)
</code></pre>

blocks|key|46054|text|如果没有内置的东西，那么编写自己的代码就很简单了：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|46055|(define+(range+first+last)
++(if+(>=+first+last)
++++++'()
++++++(cons+first+(range+(%2B+first+1)+last))))|code-block|syntax|javascript|46056|在线方案评估器：http://eval.ironscheme.net/?id=71|offset|length|46057|entityMap|0|LINK|mutability|MUTABLE|url|http://eval.ironscheme.net/?id=71^0|0|0|8|X|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

If there's nothing built-in, it's trivial to write your own:

<pre><code>(define (range first last)
 (if (&gt;= first last)
 '()
 (cons first (range (+ first 1) last))))
</code></pre>

Online scheme evaluator: <a href="http://eval.ironscheme.net/?id=71" rel="nofollow">http://eval.ironscheme.net/?id=71</a>

blocks|key|2523426|text|我只是将@Ankur的评论提升为一个答案。在球拍中，你有"+In+-range"：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2523427|#lang+racket

(in-range+7)++;;+produces+#<stream>

;;+used+in+a+loop:
(for/list+([i+(in-range+7)])
++i)
;;+produces+(list+0+1+2+3+4+5+6)


;;+and,+for+the+lazy+among+us:

(for/list+([i+7])
++i)

;;+produces+the+same|code-block|syntax|javascript|2523428|它还可以接受下限、增量(包括负数)等。|2523429|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

I'm just elevating @Ankur's comment to an answer. In Racket, you have "in-range":

<pre><code>#lang racket

(in-range 7) ;; produces #&lt;stream&gt;

;; used in a loop:
(for/list ([i (in-range 7)])
 i)
;; produces (list 0 1 2 3 4 5 6)


;; and, for the lazy among us:

(for/list ([i 7])
 i)

;; produces the same
</code></pre>

It can also accept a lower limit, an increment (including negative), etc.

blocks|key|46201|text|在Germán+Diago的评论之后，我为此做了一个纯函数的惰性版本(即流)。它可以构造您的Scheme实现可以在固定时间内处理的任意大小的范围流，还可以访问当前元素并在固定时间内推进流。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|46202|(define+%5Erange
++++(lambda+(x+y+getter)
++++++(op+x+y+getter)))

(define+EOS+;+End+of+stream+for+finite+streams
++++(%5Erange+'()+'()+(lambda+()+EOS)))

(define+range+
++++(lambda+(x+.+y)+;+if+y+<+x+then+stream+is+infinite
++++++(let+((x+(if+(null?+y)+0+x))
++++++++++++(y+(if+(null?+y)+x+(car+y))))
++++++++(%5Erange+x+y+(lambda+()
++++++++++++++++++++++(if+(=+x+y)+EOS+
+++++++++++++++++++++++(range+(%2B+x+1)+y)))))))

(define+get+;+Get+current+element
++++(lambda+(r)
++++++(r+(lambda+(x+y+g)+x))))

(define+next+;+Get+stream+for+next+element
++++(lambda+(r)
++++++(r+(lambda+(x+y+g)+(g)))))|code-block|syntax|javascript|46203|使用以下代码：|46204|>+(define+r+(range+1+3))
>+(get+r)
1
>+(get+(next+r))
2
>+(get+(next+(next+r)))
3
>+(get+(next+(next+(next+r))))+;+EOS
()|46205|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Following a comment by Germán Diago I made a pure functional lazy version (i.e. stream) for this. It can construct a range stream of any size that your Scheme implementation can handle in constant time as well as access the current element and advance the stream, also in constant time.

<pre><code>(define ^range
 (lambda (x y getter)
 (op x y getter)))

(define EOS ; End of stream for finite streams
 (^range '() '() (lambda () EOS)))

(define range 
 (lambda (x . y) ; if y &lt; x then stream is infinite
 (let ((x (if (null? y) 0 x))
 (y (if (null? y) x (car y))))
 (^range x y (lambda ()
 (if (= x y) EOS 
 (range (+ x 1) y)))))))

(define get ; Get current element
 (lambda (r)
 (r (lambda (x y g) x))))

(define next ; Get stream for next element
 (lambda (r)
 (r (lambda (x y g) (g)))))
</code></pre>

Using this code:

<pre><code>&gt; (define r (range 1 3))
&gt; (get r)
1
&gt; (get (next r))
2
&gt; (get (next (next r)))
3
&gt; (get (next (next (next r)))) ; EOS
()
</code></pre>

blocks|key|45904|text|没有找到我想要的东西，也不想使用外部包，我最终编写了自己的版本，它与python版本不同(希望在此基础上改进)。如果您认为它的效率真的很低，并且可以改进它，请这样做。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|45905|;;+A+version+of+range+taking+the+form+(range+[[first]+last+[[step]]]+).
;;+It+takes+negative+numbers+and+corrects+STEP+to+the+same+direction
;;+as+FIRST+to+LAST+then+returns+a+list+starting+from+FIRST+and
;;+ending+before+LAST
(define+(range+.+args)
++(case+(length+args)
+++(+(0)+'())
+++(+(1)+(range+0+(car+args)+(if+(negative?+(car+args))+-1+1)))
+++(+(2)+(range+(car+args)+(cadr+args)
+++++++++++++(if+(>=+(car+args)+(cadr+args))+-1+1)))
+++(+(3)+(let*+((start+(car+args))+(end+(cadr+args))+
++++++++++++++++(step+(if+(>+start+end)
++++++++++++++++++++++++++(-+(abs+(caddr+args)))+
++++++++++++++++++++++++++(abs+(caddr+args)))))
++++++++++++(let+loop+((x+start)+(xs+'()))
+++++++++++++++(cond+((and+(>=+end+start)+(<=+end+x))
++++++++++++++++++++++(reverse+xs))
+++++++++++++++++++++((and+(<=+end+start)+(>=+end+x))
++++++++++++++++++++++(reverse+xs))
+++++++++++++++++++++(else+(loop+(%2B+x+step)+(cons+x+xs)))))))
+++(else+(error+'range+"too+many+arguments"))))
;++(else+(display+"ERROR:+range+too+many+arguments")+(newline))))+;;r4rs

;;+(range-inc+[[first]+last+[[step]]]+)+includes+LAST+in+the+returned+range
(define+(range-inc+.+args)
++(case+(length+args)
++++(+(0)+'())
++++(+(1)+(append+(range+(car+args))+args))
++++(+(2)+(append+(range+(car+args)+(cadr+args))+(cdr+args)))
++++(+(3)+(append+(range+(car+args)+(cadr+args)+(caddr+args))
++++++++++++++++++(list+(cadr+args))))
++++(else+(error+'range+"too+many++arguments"))))
;+++(else+(display+"ERROR:+range+too+many+arguments")+(newline))))+;;r4rs|code-block|syntax|javascript|45906|注意，我也写了一个common+lisp版本|offset|length|45907|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/51376674/6713615^0|0|0|9|B|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

Not finding what I wanted and not wanting to have to use an external package, I ended up writing my own version which differs from the python version (hopefully improving on it). If you think it is really inefficient and can improve on it, please do.
<pre><code>;; A version of range taking the form (range [[first] last [[step]]] ).
;; It takes negative numbers and corrects STEP to the same direction
;; as FIRST to LAST then returns a list starting from FIRST and
;; ending before LAST
(define (range . args)
 (case (length args)
 ( (0) '())
 ( (1) (range 0 (car args) (if (negative? (car args)) -1 1)))
 ( (2) (range (car args) (cadr args)
 (if (&gt;= (car args) (cadr args)) -1 1)))
 ( (3) (let* ((start (car args)) (end (cadr args)) 
 (step (if (&gt; start end)
 (- (abs (caddr args))) 
 (abs (caddr args)))))
 (let loop ((x start) (xs '()))
 (cond ((and (&gt;= end start) (&lt;= end x))
 (reverse xs))
 ((and (&lt;= end start) (&gt;= end x))
 (reverse xs))
 (else (loop (+ x step) (cons x xs)))))))
 (else (error 'range &quot;too many arguments&quot;))))
; (else (display &quot;ERROR: range too many arguments&quot;) (newline)))) ;;r4rs

;; (range-inc [[first] last [[step]]] ) includes LAST in the returned range
(define (range-inc . args)
 (case (length args)
 ( (0) '())
 ( (1) (append (range (car args)) args))
 ( (2) (append (range (car args) (cadr args)) (cdr args)))
 ( (3) (append (range (car args) (cadr args) (caddr args))
 (list (cadr args))))
 (else (error 'range &quot;too many arguments&quot;))))
; (else (display &quot;ERROR: range too many arguments&quot;) (newline)))) ;;r4rs
</code></pre>
Note I wrote a <a href="https://stackoverflow.com/a/51376674/6713615">common lisp</a> version as well

How to create a list of consecutive numbers in Scheme?

In Python to create a list of integers from 1 to 10 would be <code>range(1,11)</code>. Is there an equivalent for Scheme?

<code>mzscheme --version</code> gives <code>Welcome to Racket v5.2.1.</code>

Edit: Per <a href="https://stackoverflow.com/a/7144310/596361">https://stackoverflow.com/a/7144310/596361</a> to implement range functionality, this code is needed:

<pre><code>#lang racket
(require srfi/1)
(iota 5 1)
</code></pre>

Analog of Python's range in Scheme

如何在Scheme中创建连续数字列表？在Python语言中，创建一个从1到10的整数列表的方法是range(1,11)。是否有与Scheme等效的方案？mzscheme --version给了Welcome to Racket v5.2.1.编辑:每个的要实现范围功能，需要以下代码：#lang racket(require srfi/1)(iota 5 1)

问在Scheme中模拟Python的范围
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