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JavaScript Regular Expressions in JavaScript Regular Expressions Groups

Victor Stanciu
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Victor Stanciu
Full Stack JavaScript Techdegree Student 11,196 Points
Posted by Victor Stanciu
.a{fill-rule:evenodd;}techdegree
Victor Stanciu
Full Stack JavaScript Techdegree Student 11,196 Points

My solution

This is my solution for the practice:

  1. Match "img_0" followed by a number, then a dot, then either "jpg", "png" or "gif": img_0\d\.(jpg|png|gif)

  2. Match "pro" followed by either "jec", "trac" or "c" then followed by "tor": pro(jec|trac|c)tor

  3. Match "img_" followed by either "sm" or "0<and a number>", then followed by either "_0<and a number>" or nothing, then followed by a dot, then followed by either "jpg" or "png": img_(sm|0\d)(_0\d)?\.(jpg|png)

  4. Match either "www" or "api" followed by a dot, or nothing at all, then followed by either "github" or "teamtreehouse", then followed by a dot then followed by "com": ((www|api)\.)?(github|teamtreehouse)\.com

Hope this helps!

Darrel Valdiviezo
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Darrel Valdiviezo
Full Stack JavaScript Techdegree Student 11,407 Points
Darrel Valdiviezo
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Darrel Valdiviezo
Full Stack JavaScript Techdegree Student 11,407 Points

Hey Victor,

Thanks for sharing!

here are my soultions:

1st answer: img_0[\d.]\.(jpg|png|gif)

1st answer alternative: [\w]*\.(jpg|png|gif)

2nd answer: pro(j|t|c)[\w]+

3rd answer: [\w]+\.(jpg|png)

4th answer: (www\.|api\.)?[\w]+\.com ...Victor Stanciu your double group to capture the "." was a nice touch - i duplicated mine :(

1 Answer

Jason Larson
Jason Larson
8,352 Points
Jason Larson
Jason Larson
8,352 Points

I know this lesson was on grouping, but it seems like overkill for numbers 3 and 4. For number 3, all the ones to include had "img_" and something, and the one to exclude didn't have an underscore, so img_.+ works for the given test cases. Again, with number 4, all the grouping seems like overkill, as the ones to be excluded end in ".net" and the ones to match end in ".com", so .+\.com$ gets all but the ones ending in ".net". It would be nice if they gave more explicit details on what to match and exclude, and/or gave broader test sets.