Python如何拆行长单行字符串且不插入多余空格或换行？

你遇到的问题是在代码中拆分单行长字符串时，容易引入多余缩进空格，现有方案你觉得可维护性不高，下面给出两种不同场景下的简便方案：

方案1：编译期隐式拼接（推荐，性能最高） #

你提到的括号包裹多个字符串字面量的写法其实是Python官方推荐的标准方案，它的拼接逻辑在编译阶段就完成，运行时没有任何额外开销，可维护性差的问题只需要调整写法习惯就能规避：

• 统一将空格放在每一行字符串的末尾，调整后的写法如下：

long_string = (
    "This is a very long string. "
    "Since it is a one-line string, I really want "
    "to keep it without any new line. However, I don't like how "
    "it looks in my code and it is annoying me"
)

这种写法后续增删字符串行只需要对应维护当前行末尾的空格即可，非常直观，也不需要额外导入依赖。

方案2：文档字符串清理（适合超长字符串，写起来最省事） #

如果字符串长度非常长，不想每一行都加引号，可以用标准库的inspect.cleandoc自动清理公共缩进，再替换换行符为空格即可：

import inspect

long_string = inspect.cleandoc("""
    This is a very long string. Since it is a one-line string, I really want
    to keep it without any new line. However, I don't like how it looks in my
    code and it is annoying me
""").replace('\n', ' ')

cleandoc会自动去掉所有行前的公共缩进，再把换行符替换为单个空格，就能得到没有多余字符的单行字符串，写的时候不需要额外处理每行的引号，改起来更方便。

不推荐的写法 #

你之前用的反斜杠换行的写法，只要删掉第二行开始的缩进就能避免多余空格，但这种写法容错性极低，反斜杠后不能有任何空格、注释，非常容易出BUG，Python社区普遍不推荐使用：

# 可以运行但不推荐
long_string = "This is a very long string. Since it is a one-line string, I really want \
to keep it without any new line. However, I don't like how it looks in my \
code and it is annoying me"

内容的提问来源于stack exchange，提问作者Pagly