RegEx : Capturing words within Quotation mark

Question

I have a paragraph of text like this:

John went out for a walk. He met Mrs. Edwards and said, 'Hello Mam how are you doing today?'. She replied 'I'm fine. How are you?'.

I would like to capture the words within the single quotes. I tried this regex

re.findall(r"(?<=([']\b))((?=(\\?))\2.)*?(?=\1))",string)

(from this question: RegEx: Grabbing values between quotation marks)

It returned only single quotes as the output. I don't know what went wrong can someone help me?

Running your code gives me "cannot refer to open group" error. https://regex101.com/r/FNt7rO/1 — CertainPerformance, Sep 17 '18 at 02:00
@Tim This regex *is* wrong. `\2` is referring to the capturing group itself is in. — iBug, Sep 17 '18 at 02:05
@TimBiegeleisen That's the error I get when I run OP's code in Python (which is separate from the unbalanced parentheses) — CertainPerformance, Sep 17 '18 at 02:05
@iBug the sample output: Hello Mam how are you doing today? , I'm fine. How are you?. It should be displayed without the quotes — mrutula suresh, Sep 17 '18 at 02:37

Pedro Lobito · Accepted Answer · 2018-09-23T10:14:11.733

2

Python requires capturing groups to be fully closed before any backreferences (\2) to the group.

You can use Positive Lookbehind (?<=[\s,.]) and Positive Lookahead (?=[\s,.]) zero-length assertions to match words inside single quotes, including words such as I'm, i.e.:

re.findall(r"(?<=[\s,.])'.*?'(?=[\s,.])", string)

Full match  56-92   'Hello Mam how are you doing today?'
Full match  106-130 'I'm fine. How are you?'

Explanation

Regex Demo

edited Sep 23 '18 at 10:14

answered Sep 17 '18 at 02:12

Pedro Lobito

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Closing double quote is missing, I think. – NickD Sep 17 '18 at 02:48
@NickD, I've tested the code above and it works as expected. – Pedro Lobito Sep 17 '18 at 09:40
>>> re.findall(r"(?<=[\s,.])'.*?'(?=[\s,.]), string) File "", line 1 re.findall(r"(?<=[\s,.])'.*?'(?=[\s,.]), string) ^ SyntaxError: EOL while scanning string literal – NickD Sep 19 '18 at 16:29

RegEx : Capturing words within Quotation mark

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