正如PEP8所建议的那样,在python程序中保持低于80列的规则,对于长字符串,我怎么能遵守这个规则呢?

s = "this is my really, really, really, really, really, really, really long string that I'd like to shorten."

我该如何把它扩展到下面一行呢?

s = "this is my really, really, really, really, really, really" + 
    "really long string that I'd like to shorten."

当前回答

隐式连接可能是最干净的解决方案:

s = "this is my really, really, really, really, really, really," \
    " really long string that I'd like to shorten."

编辑经过反思,我同意托德的建议,使用括号而不是行接续更好,因为他给出了所有的理由。我唯一的犹豫是,用括号括起来的字符串和元组比较容易混淆。

其他回答

可用的选项:

反斜杠:"foo" \ "bar" "foo" + " \ "bar" 括号: (“foo”“酒吧”) 带加号的括号:("foo" + "bar") PEP8, E502:括号之间的反斜杠是多余的

避免

避免使用逗号:("foo", "bar")来定义一个元组。


>>> s = "a" \
... "b"
>>> s
'ab'
>>> type(s)
<class 'str'>
>>> s = "a" + \
... "b"
>>> s
'ab'
>>> type(s)
<class 'str'>
>>> s = ("a"
... "b")
>>> type(s)
<class 'str'>
>>> print(s)
ab
>>> s = ("a",
... "b")
>>> type(s)
<class 'tuple'>
>>> s = ("a" + 
... "b")
>>> type(s)
<class 'str'>
>>> print(s)
ab
>>> 

我以前用过textwrap.dedent。这有点麻烦,所以我现在更喜欢行延续,但如果你真的想要块缩进,我认为这很好。

示例代码(其中trim是去掉带有切片的第一个'\n'):

import textwrap as tw
x = """\
       This is a yet another test.
       This is only a test"""
print(tw.dedent(x))

解释:

Dedent根据新行前第一行文本中的空白计算缩进。如果你想调整它,你可以使用re模块轻松地重新实现它。

这种方法有局限性,很长的行可能仍然比你想要的长,在这种情况下,其他方法连接字符串更适合。

使用\你可以将语句扩展到多行:

s = "this is my really, really, really, really, really, really" + \
"really long string that I'd like to shorten."

应该工作。

反斜杠:

s = "this is my really, really, really, really, really, really" +  \
    "really long string that I'd like to shorten."

或者用括号括起来:

s = ("this is my really, really, really, really, really, really" + 
    "really long string that I'd like to shorten.")

隐式连接可能是最干净的解决方案:

s = "this is my really, really, really, really, really, really," \
    " really long string that I'd like to shorten."

编辑经过反思,我同意托德的建议,使用括号而不是行接续更好,因为他给出了所有的理由。我唯一的犹豫是,用括号括起来的字符串和元组比较容易混淆。