正则表达式提取所有以相同单词开头和结尾的句子

Question

Given a string of sentences, I need to extract a list of all of the sentences which start and end with the same word.

eg

# sample text
text = "This is a sample sentence. well, I'll check that things are going well. another sentence starting with another. ..."

# required result
[
 "well, I'll check that things are going well",
 "another sentence starting with another"
]

How can I make the match using back references and also capture the full sentence?

I have tried the following regex but it's not working.

re.findall("^[a-zA-Z](.*[a-zA-Z])?$", text)

Answer 1

text = "This is a sample sentence. going to checking whether it is well going. another 
sentence starting with another."

sentences = re.split('[.!?]+', text)
result = []

for s in sentences:
    words = s.split()
    if len(words) > 0 and words[0] == words[-1]:
        result.append(s.strip())

print(result)

Answer 2

You could try using a backreference to reuse the match...

import re

# sample text
text = "This is a sample sentence. Well, I'll check that things are going well. another sentence starting with another. ..."

print([match[0] for match in re.findall(r"((\b\w+\b)[^.?!]+\2[.?!])", text, re.IGNORECASE)])

This prints...

['Well, I'll check that things are going well.', 'another sentence starting with another.']

Note: I changed the case of the first "well" to "Well" for testing purposes.