blocks|key|397397|text|你想做的事：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|397398|chps+=+[str(x)
++++++++for+entry+in+chapters.split(',')
++++++++for+x+in+(chp_range(entry)+if+'-'+in+entry+else+[entry])]|code-block|syntax|javascript|397399|在网上试试！|offset|length|397400|entityMap|0|LINK|mutability|MUTABLE|url|https://tio.run/##VY7fCoIwFMbv9xTnbhvNQIsIoScRiWUzBzbH2Qn06demSPRdHTi/749faJjc6eoxxm7QngwGuAEvVaXOxUWVFWfsaXroBn9H7V5GBFkzSNIKHgl9ay@sIwXhGPxoSfCCS7kSaOiDDjZbxg@lZCwl5YomEIp5A7P6CcE4wgWsg33KHqn4PzhnSPw2rUYJtofUnn9bkhmDgWa9W9ky5jEtzbYgY/wC^0|0|0|0|6|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]]]]

What you were trying to do:
<pre><code>chps = [str(x)
 for entry in chapters.split(',')
 for x in (chp_range(entry) if '-' in entry else [entry])]
</code></pre>
<a href="https://tio.run/##VY7fCoIwFMbv9xTnbhvNQIsIoScRiWUzBzbH2Qn06demSPRdHTi/749faJjc6eoxxm7QngwGuAEvVaXOxUWVFWfsaXroBn9H7V5GBFkzSNIKHgl9ay@sIwXhGPxoSfCCS7kSaOiDDjZbxg@lZCwl5YomEIp5A7P6CcE4wgWsg33KHqn4PzhnSPw2rUYJtofUnn9bkhmDgWa9W9ky5jEtzbYgY/wC" rel="nofollow noreferrer" title="Python 3.8 (pre-release) – Try It Online">Try it online!</a>

blocks|key|787318|text|如果它必须是一个单线，这应该是可行的：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|787319|>>>+[str(x)+for+c+in+chapters.split(",")+for+x+in+range(int(c.split("-")[0]),+int(c.split("-")[-1])%2B1)]
['1',+'2',+'4',+'5',+'6',+'12']|code-block|syntax|javascript|787320|你不能有条件地嵌套你的理解，所以你的chp_range函数在理解中没有什么价值。|offset|length|style|CODE|787321|entityMap^0|0|0|I|9|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

If it has to be a one-liner, this should work:
<pre><code>&gt;&gt;&gt; [str(x) for c in chapters.split(&quot;,&quot;) for x in range(int(c.split(&quot;-&quot;)[0]), int(c.split(&quot;-&quot;)[-1])+1)]
['1', '2', '4', '5', '6', '12']
</code></pre>
You can't conditionally nest your comprehensions, so your <code>chp_range</code> function is of little value when used in a comprehension.

blocks|key|787291|text|只有在列表实际上更容易/更易读的情况下，才可以尝试使用列表理解：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|787292|lst+=+[]
for+x+in+s.split(','):+
++++if+'-'+in+x:
++++++++start,+end+=+x.split('-')
++++++++lst.extend([str(i)+for+i+in+range(int(start),+int(end)%2B1)])
++++else:
++++++++lst.append(x)|code-block|syntax|javascript|787293|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Don't try to use list comprehension for the sake of, only if it's actually easier / more readable:
<pre><code>lst = []
for x in s.split(','): 
 if '-' in x:
 start, end = x.split('-')
 lst.extend([str(i) for i in range(int(start), int(end)+1)])
 else:
 lst.append(x)
</code></pre>

blocks|key|787342|text|from+itertools+import+chain


def+chp_range(entry):
++++x,+y+=+map(int,+entry.split('-'))
++++return+map(str,+range(x,+y%2B1))


chps+=+[
++++chp_range(entry)+if+'-'+in+entry+else+entry+for+entry+in+chapters.split(',')]
list(chain(*chps))|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|787343|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>from itertools import chain


def chp_range(entry):
 x, y = map(int, entry.split('-'))
 return map(str, range(x, y+1))


chps = [
 chp_range(entry) if '-' in entry else entry for entry in chapters.split(',')]
list(chain(*chps))
</code></pre>

blocks|key|391692|text|YOu可以将扩展用于范围，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|391693|string+=+'1,2,4-6,12'
string+=+string.split(',')
chapters+=+[]+
for+i+in+string:
++++if+'-'+in+i:
++++++++a,b+=+i.split('-')
++++++++chapters.extend(range(int(a),int(b)%2B1))
++++else:
++++++++chapters.append(int(i))
print(chapters)|code-block|syntax|javascript|391694|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

YOu can use extend for range as follows:
<pre><code>string = '1,2,4-6,12'
string = string.split(',')
chapters = [] 
for i in string:
 if '-' in i:
 a,b = i.split('-')
 chapters.extend(range(int(a),int(b)+1))
 else:
 chapters.append(int(i))
print(chapters)

</code></pre>

blocks|key|397402|text|不是单行，而是如果您对递归解决方案感兴趣的话。请检查一下。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|397403|a+=+'1,2,4-6,12'
inp+=+[num++if+'-'+not+in+num+else+[str(i)+for+i+in+range(int(num[0]),int(num[-1])%2B1)]+for+num+in+a.split(',')+]
ans+=+[]

def+flatten(inp,ans):

++while+inp:
++++tmp+=+inp.pop()

++++if+type(tmp)+==+str:
++++++ans.append(tmp)
++++else:
++++++flatten(tmp,ans)

++return+

flatten(inp,ans)

ans[::-1]|code-block|syntax|javascript|397404|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Not a one-liner but if you are interested in a recursive solution. Please check it up.
<pre><code>a = '1,2,4-6,12'
inp = [num if '-' not in num else [str(i) for i in range(int(num[0]),int(num[-1])+1)] for num in a.split(',') ]
ans = []

def flatten(inp,ans):

 while inp:
 tmp = inp.pop()

 if type(tmp) == str:
 ans.append(tmp)
 else:
 flatten(tmp,ans)

 return 

flatten(inp,ans)

ans[::-1]
</code></pre>

I have a CSV file that contains book chapters either as single chapters or chapter ranges delimited by commas, e.g. <code>1,2,4-6,12</code>.
Given this input <code>'1,2,4-6,12'</code>, I want a list <code>['1','2','4','5','6','12']</code> as output
Something along the lines of:
<pre class="lang-py prettyprint-override"><code>chps=[str(x) for x in chp_range(entry)) if '-' in entry else entry for entry in chapters.split(',') ]
</code></pre>
which doesn't work.
Function <code>chp_range('4-6')</code> returns a <code>range(4,6)</code> object.
I've tried a lot of variations, but still haven't been able to get the order of conditionals and iteration right. How can I get this code to work?

List comprehension if/else and for iteration order

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我有一个CSV文件，它包含图书章节，或者是单个章节，或者是由逗号分隔的章节范围，例如1,2,4-6,12。给定这个输入'1,2,4-6,12'，我想要一个列表['1','2','4','5','6','12']作为输出与…有关的东西：chps=[str(x) for x in chp_range(entry)) if '-' in entry else entry  for entry in ch

问列出如果/else和迭代顺序的理解
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