Regular Expressions 101

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/
foo: \K.*
/
foo:
matches the characters foo: literally (case sensitive)
\K resets the starting point of the reported match. Any previously consumed characters are no longer included in the final match
.
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)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/

Test String

Substitution

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