Regular Expressions 101

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"
^.[^0-9.][a-z.\s]*|(\s?[(].*?[)]|\s)$
"
gmx
1st Alternative
^.[^0-9.][a-z.\s]*
^ asserts position at start of a line
. matches any character (except for line terminators)
Match a single character not present in the list below
[^0-9.]
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
Match a single character present in the list below
[a-z.\s]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\s matches any whitespace character (equivalent to [\r\n\t\f\v  ])
2nd Alternative
(\s?[(].*?[)]|\s)$
1st Capturing Group
(\s?[(].*?[)]|\s)
1st Alternative
\s?[(].*?[)]
\s
matches any whitespace character (equivalent to [\r\n\t\f\v  ])
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[(]
( matches the character ( with index 4010 (2816 or 508) literally (case sensitive)
.
matches any character (except for line terminators)
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
Match a single character present in the list below
[)]
) matches the character ) with index 4110 (2916 or 518) literally (case sensitive)
2nd Alternative
\s
\s matches any whitespace character (equivalent to [\r\n\t\f\v  ])
$ asserts position at the end of a line
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
x modifier: extended. Spaces and text after a # in the pattern are ignored
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"
gmx

Test String

Substitution

Processing...