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JavaScript Regular Expressions in JavaScript Regular Expressions Excluding Characters

karan Badhwar
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karan Badhwar
Web Development Techdegree Graduate 18,135 Points
Posted by karan Badhwar
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karan Badhwar
Web Development Techdegree Graduate 18,135 Points

[^@.] + vs [^@.]*

Why the output is different if I put * (asterisk) instead of + plus?

1 Answer

Megan Amendola
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Megan Amendola
Treehouse Teacher
Megan Amendola
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Megan Amendola
Treehouse Teacher

In regex, + means it is looking for one or more while * means it is looking for zero or more.

I like to play around with my Regex on this site to check how it is working and test my work.

karan Badhwar
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karan Badhwar
Web Development Techdegree Graduate 18,135 Points
karan Badhwar
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karan Badhwar
Web Development Techdegree Graduate 18,135 Points

Hi Megan Amendola, Thankyou for your response. Actually, the results were weird, if I go as per the video and just change the + to *. The results were different. Where with + it was showing 3 matches, but with * it was 4 that's what I did not understand. I tried on the website given by you with

[^@.]+ 
[^@.]*

and the string was

toy@boat.com

With the First I got 3 matches, but with the second I got a warning.