Regular Expressions 101

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/
<(ul|ol)>\s*<li>{([ .\w-]+)} *(.*?)<\/\1>
/
gms
< matches the character < with index 6010 (3C16 or 748) literally (case sensitive)
1st Capturing Group
(ul|ol)
1st Alternative
ul
ul
matches the characters ul literally (case sensitive)
2nd Alternative
ol
ol
matches the characters ol literally (case sensitive)
> matches the character > with index 6210 (3E16 or 768) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v ])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
<li>{
matches the characters <li>{ literally (case sensitive)
2nd Capturing Group
([ .\w-]+)
Match a single character present in the list below
[ .\w-]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
.
matches a single character in the list . (case sensitive)
\w matches any word character (equivalent to [a-zA-Z0-9_])
- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
This hyphen is treated literally, which might be confusing for others. Consider escaping it or placing at the start or end of the class!
} matches the character } with index 12510 (7D16 or 1758) literally (case sensitive)
matches the character with index 3210 (2016 or 408) literally (case sensitive)
3rd Capturing Group
(.*?)
.
matches any character
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
< matches the character < with index 6010 (3C16 or 748) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
\1 matches the same text as most recently matched by the 1st capturing group
> matches the character > with index 6210 (3E16 or 768) literally (case sensitive)
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)
s modifier: single line. Dot matches newline characters
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gms

Test String

Regex Debugger

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