Regular Expressions 101

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`
https?://w*[[:punct:]]?([^/]+)/?
`
g
http
matches the characters http literally (case sensitive)
s
matches the character s with index 11510 (7316 or 1638) literally (case sensitive)
://
matches the characters :// literally (case sensitive)
w
matches the character w with index 11910 (7716 or 1678) literally (case sensitive)
Match a single character present in the list below
[[:punct:]]
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
[:punct:] matches a punctuation character [!"#$%&'()*+,\-./:;<=>?@[\]^_`{|}~]
1st Capturing Group
([^/]+)
Match a single character not present in the list below
[^/]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
/
matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
Your regular expression does not match the subject string.

Regular Expression
No Match

`
`
g

Test String