如何写非常长的符合PEP8和防止E501的字符串

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

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。

其他回答

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。

您丢失了一个空格，您可能需要一个行延续字符，即。一个\。

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

甚至:

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

parns也可以代替行续符，但可能会有人认为您打算使用元组，而只是忘记了逗号。举个例子:

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

对比:

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

使用Python的动态类型，代码可以以任何一种方式运行，但会产生不正确的结果。

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。

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。

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.")

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