在Python中包装多行字符串（保留现有的换行符）？(Wrap multiline string (preserving existing linebreaks) in Python?)

 考虑这个例子： 
 
import textwrap
import pprint

mystr=r"""
First line.
Second line.
The third line is a very long line, which I would like to somehow wrap; wrap at 80 characters - or less, or more! ... can it really be done ??"""

pprint.pprint(textwrap.wrap(mystr,80))
 
 字符串mystr已经是一个多行字符串，因为它包含换行符; 但是，如果我运行此脚本，我得到输出： 
 
[' First line. Second line. The third line is a very long line, which I would like',
 'to somehow wrap; wrap at 80 characters - or less, or more! ... can it really be',
 'done ??']
 
 ...这意味着textwrap.wrap首先“加入”多行字符串（即删除其中的现有换行符），然后才将其包装（即将其拆分为给定的字符数）。 
 
 如何包装多行字符串，以便保留换行符？ 也就是说，在这种情况下，预期输出将是： 
 
['First line.', 
 'Second line.', 
 'The third line is a very long line, which I would like to somehow wrap; wrap at',
 '80 characters - or less, or more! ... can it really be done ??']
 
 
 编辑; 感谢@u_mulder的评论，我试过： 
 
textwrap.wrap(mystr,80,replace_whitespace=False)
 
 我得到了： 
 
['\nFirst line.\nSecond line.\nThe third line is a very long line, which I would like',
 'to somehow wrap; wrap at 80 characters - or less, or more! ... can it really be',
 'done ??']
 
 换行似乎被保留，但作为“内联”字符; 所以这里第一个元素本身就是一个多行字符串 - 所以它不是我需要的，每一行都是一个数组元素。 

Consider this example:
 
import textwrap
import pprint

mystr=r"""
First line.
Second line.
The third line is a very long line, which I would like to somehow wrap; wrap at 80 characters - or less, or more! ... can it really be done ??"""

pprint.pprint(textwrap.wrap(mystr,80))
 
The string mystr is already a multiline string, given that it contains linebreaks; however, if I run this script, I get as output:
 
[' First line. Second line. The third line is a very long line, which I would like',
 'to somehow wrap; wrap at 80 characters - or less, or more! ... can it really be',
 'done ??']
 
... which means that textwrap.wrap first "joined" the multiline string (that is, removed the existing linebreaks in it), and only then wrapped it (i.e. split it at the given number of characters). 
 
How can I wrap a multiline string, such that the line feeds are preserved? that is, in this case, the expected output would be:
 
['First line.', 
 'Second line.', 
 'The third line is a very long line, which I would like to somehow wrap; wrap at',
 '80 characters - or less, or more! ... can it really be done ??']
 
 
EDIT; thanks to comment by @u_mulder, I tried:
 
textwrap.wrap(mystr,80,replace_whitespace=False)
 
and with that I get:
 
['\nFirst line.\nSecond line.\nThe third line is a very long line, which I would like',
 'to somehow wrap; wrap at 80 characters - or less, or more! ... can it really be',
 'done ??']
 
The line breaks seem to be preserved, but as "inline" characters; so here the first element is a multiline string in itself -- and so it is not as I require it, with every line as an array element.

原文：https://stackoverflow.com/questions/28863889