What are lookaheads in regexes?

JavaScript
1

What are lookaheads in regexes?

2

they are non-capturing groups that look after the captured pattern (and actually capture it only if the lookahead is respected)

https://www.regular-expressions.info/lookaround.html

1 Like
3

Thanks for the response.

4

in Regular Expressions: Positive and Negative Lookahead https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/regular-expressions/positive-and-negative-lookahead

I have this code:

let sampleWord = "astronaut";
let pwRegex = /(?=\w{5})(?=\d?=\d)/; // Change this line
let result = pwRegex.test(sampleWord);

Some help with this please, as it doesn’t pass the tests.

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there is repeated code inside here, should they be two different lookaheads or the pattern you are checking is actually \d?=\d (as in, digit, question mark, equal sign, digit)?

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I am not sure about that.