Regular Expressions 101

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`
http://(.*)\.eleveo.com/auth(/)?
`
gm
http://
matches the characters http:// literally (case sensitive)
1st Capturing Group
(.*)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
eleveo
matches the characters eleveo literally (case sensitive)
. matches any character (except for line terminators)
com/auth
matches the characters com/auth literally (case sensitive)
2nd Capturing Group
(/)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
/ 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)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match

`
`
gm

Test String

Substitution

Processing...