如何编写匹配独立字母i的正则表达式及Python查找脚本？

需求 #

仅定位并修正孤立存在或作为第一人称单数代词的小写字母i，忽略单词内部的i（比如with、time中的i无需处理）。

正则表达式 #

使用负向零宽断言精准匹配目标i：

(?<!\w)i(?!\w)

规则解释 #

• (?<!\w)：确保i的前一个字符不是单词字符（字母、数字、下划线）
• i：匹配目标小写字母
• (?!\w)：确保i的后一个字符不是单词字符

该表达式会匹配句子开头的i、单独作为主语的i（如i am中的i），但不会匹配单词内部的i。

Python脚本实现 #

以下脚本可自动将文本中符合要求的小写i替换为大写I：

import re

def correct_i_case(text):
    # 定义匹配规则
    pattern = r'(?<!\w)i(?!\w)'
    # 替换匹配到的i为I
    return re.sub(pattern, 'I', text)

# 测试用原始文本
raw_text = """with this notice know that i inscribe messages to inform.
a boy named "Will" said into a microphone that time is like a high-five.
i give lines to computers to find cities and sites. 
i am my eyes, and to view is to exist (cuanda tu ve, tu comprendes el significado del 'hay')
view that i will not be processing your application any further because i am eating an apple."""

# 执行修正
corrected_text = correct_i_case(raw_text)

# 输出结果
print("修正后文本：")
print(corrected_text)

运行效果 #

修正后的文本会将所有需要大写的i改为I，单词内部的i保持原样，示例输出如下：

with this notice know that I inscribe messages to inform.
a boy named "Will" said into a microphone that time is like a high-five.
I give lines to computers to find cities and sites. 
I am my eyes, and to view is to exist (cuanda tu ve, tu comprendes el significado del 'hay')
view that I will not be processing your application any further because I am eating an apple.

内容的提问来源于stack exchange，提问作者Toothpick Anemone