Capture repeated groups in python regex

Question

I have a mail log file, which is like this:

Aug 15 00:01:06 **** sm-mta*** to=,

        

Answer 1

Try regex module.

x="""Aug 15 00:01:06 **** sm-mta*** to=,,user3@aol.com, some_more_stuff
Aug 16 13:16:09 **** sendmail*** to=, some_more_stuff
Aug 17 11:14:48 **** sm-mta*** to=,, some_more_stuff"""
import regex
print regex.findall(r"sm-mta.*to=\K|\G(?!^).+?@(.*?)[>, ]", x, version=regex.V1)

Output: ['', 'gmail.com', 'yahoo.com', 'aol.com', '', 'gmail.com', 'gmail.com']

Just ignore the first empty match.

https://regex101.com/r/7zPc6j/1