Allow changing regular expression options not at the start of the string

Ideas
1

Today Pythong does not allow changing regex options which happen to be not at the start of the string. For instance:

import re
s = "I luv Python and CPython"
matches = re.finditer(r"\b(?i)[A-Z](?-i)[a-z]+\b", s)

As you can see, the first character in the bounded string can be of any case (?i), but starting from the second character, all of them must be in lower-case since (?-i) cancels insensitiveness of the first option. In .NET it gives expected result:

'luv'
'Python'
'and'

CPython was excluded because second character P is upper-case, when it must be lower-case.
Is it possible to realize same in Python?

2

You can, you just have to do it like the documentation describes.

This

import re

s = "I luv Python and CPython"
matches = re.finditer(r"(?i)\b[A-Z](?-i:[a-z]+)\b", s)
print([m.group(0) for m in matches])

Gives you this

['luv', 'Python', 'and']
3

You can use scoped modifiers:

r"\b(?i:[A-Z])[a-z]+\b"
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