freeCodeCamp Challenge Guide: Match Single Characters Not Specified

Match Single Characters Not Specified

Problem Explanation

In this challenge, we are asked to return a collection of matches that are not exactly specified. Whereas previous regexp challenges would have you match within the character case [a-z], this challenge instead asks us to negate these matches using the caret character [^a-z]. Our goal then is to return a negated collection (non-matches) of letters that are not vowels nor numbers.


Hint 1

Did you remember to surround your regexp in both brackets and slashes?

let exampleRegExp = /[^a-z]/;

If so, then double check you’re adding the appropriate flags:

  • i : Ignores upper and lower case from search/match
  • g : Retrieves multiple values; default is set to return the first match it encounters
  • ^ : Negates the matches following this flag

Hint 2

Be sure to check whether your number range is correct – the challenge asks us to negate all numbers from 0 to 9. This can be done using the negate caret placed immediately after the first opening bracket of your regexp.

let numbersRegExp = /[^0-9]/gi;


Solution 1 (Click to Show/Hide)
let quoteSample = "3 blind mice.";
let myRegex = /[^aeiou^0-9]/gi; // Change this line
let result = quoteSample.match(myRegex); // Change this line
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