regexp logic and or

Question

I know there are logical operators such as | "the OR operator" which can be used like this:

earth|world

I was wondering how I could check if my string contains earth AND world.

regards, alexander

duplicate http://stackoverflow.com/questions/469913/regular-expressions-is-there-an-and-operator — KJYe.Name, Mar 03 '11 at 03:44

score 47 · Accepted Answer · edited Nov 10 '22 at 08:36

47

If it contains earth AND world, it contains one after the other, so:

earth.*world|world.*earth

A shorter alternative (using extended regex syntax) would be:

/^(?=.*?earth)(?=.*?world)/

But it is not at all like an and operator. You can only do or because if only one of the words is included, there is no ordering involved. If you want to have them both, you need to indicate the order.

edited Nov 10 '22 at 08:36

Walf

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answered Mar 03 '11 at 03:42

markijbema

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I wouldn't call the second version hackish - on the contrary, especially if more than two conditions are involved, I find sequential lookaheads much more straightforward. – Tim Pietzcker Mar 03 '11 at 07:49

score 6 · Answer 2 · answered Mar 04 '11 at 17:45

6

do two tests, if the first fails the second doesn't execute in javascript. e.g.

var hasBoth = /earth/i.test(aString) && /world/i.test(aString);

answered Mar 04 '11 at 17:45

Walf

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not always convenient, would be nice to know how to do this with one regex – Alexander Mills Dec 31 '16 at 05:28

score 5 · Answer 3 · edited May 23 '17 at 10:31

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This question was asked and answered here:

Regular Expressions: Is there an AND operator?

There isn't a direct "and" operator, but you can continue expression testing and ensure the second expression is also a match.

edited May 23 '17 at 10:31

Community

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answered Mar 03 '11 at 03:41

iivel

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score 1 · Answer 4 · answered Jan 18 '20 at 17:44

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you don't need & operator actually | operator does the job

let string = 'world and earth are awesome';
let regex = /world|earth/ig;

let result = string.replace(regex, '...');

console.log(string);
console.log(result);

answered Jan 18 '20 at 17:44

Eissa Saber

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regexp logic and or

4 Answers4