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JavaScript Regular Expressions in JavaScript Regular Expressions Matching Specific Characters

Posted by tjeiosajfdksl
tjeiosajfdksl
Courses Plus Student 8,981 Points

I can not match #4 please help

My regex is :

/[lf]ad[yi][bn][ug]g?[ rug!]?/

it is supposed to match both these strings but does not match second one:

ladybug fading rug!

How to get the regex to also match : fading rug!

7 Answers

Nathan Brenner
Nathan Brenner
35,844 Points
Nathan Brenner
Nathan Brenner
35,844 Points

Another possible solution: /[fl]adi?n?[gy] ?[br]ug!?/

As far as figuring out how to get from the first case to the second, I wrote the first case into the regex expression, then I added another test case and changed the regex.

For example, started with /ladybug/ and only testing for ladybug and fading rug!, ladybug passes but fading rug ! fails, so I added another test case fadybug and changed the regex to [fl]adybug. I ended up added 6 additional test cases. To go a step further, I would want to keep changing the regex so it only matches the first two cases.

Chirag Mehta
Chirag Mehta
15,332 Points
Chirag Mehta
Chirag Mehta
15,332 Points 
[fl]ad[iy]n?g? ?[br]ug!?
L Haney
seal-mask
.a{fill-rule:evenodd;}techdegree
L Haney
Front End Web Development Techdegree Student 10,263 Points
L Haney
.a{fill-rule:evenodd;}techdegree
L Haney
Front End Web Development Techdegree Student 10,263 Points

Here's my answer:

/[lf]adi?n?[gy][ ]?[br]ug!?/
Andrew Phythian
Andrew Phythian
19,747 Points
Andrew Phythian
Andrew Phythian
19,747 Points

Here's mine...

/[lf]ad[yi]b?[un]g ?r?u?g?!?/
Martin Bort
Martin Bort
851 Points
Martin Bort
Martin Bort
851 Points

my answer was

/[lf]adi?n?g?y? ?[br]ug!?/

bare in mind, only one character inside a square bracket will ever be used.

so if you have [rug!] like you have, it will only try to match either 'r', 'u' or 'g'. Never the whole string 'rug'

Vivian Rydh
Vivian Rydh
8,873 Points
Vivian Rydh
Vivian Rydh
8,873 Points

[lf]ad[yi][bn][ug][g ]r?u?g?!?