Regular Expressions 101

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/
^http(s)?:\/\/www.example\.com
/
g
^ asserts position at start of the string
http
matches the characters http literally (case sensitive)
1st Capturing Group
(s)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
s matches the character s with index 11510 (7316 or 1638) literally (case sensitive)
: matches the character : with index 5810 (3A16 or 728) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
www
matches the characters www literally (case sensitive)
. matches any character (except for line terminators)
example
matches the characters example literally (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
com
matches the characters com 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.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
g

Test String

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