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This article is about how to use the null value to merge js. The contents of the operator. Xiaobian thinks it is quite practical, so share it with everyone for reference. Let's follow Xiaobian and have a look.

null consolidation operator

When we want to check whether a variable is null or undefined,?? Operators are useful. When its left operand is null or undefined, it returns the operand to its right, otherwise it returns the operand to its left.

const foo = null ?? 'Hello';console.log(foo); // 'Hello'const bar = 'Not null' ?? 'Hello';console.log(bar); // 'Not null'const baz = 0 ?? 'Hello';console.log(baz); // 0

In the third example, 0 is returned because even though 0 is considered false in JS, it is not null or undefined. You might think we could use|| operators, but there's a difference between the two.

You might think we could use it here.|| operator, but there is a difference between the two.

const cannotBeZero = 0 || 5;console.log(cannotBeZero); // 5const canBeZero = 0 ?? 5;console.log(canBeZero); // 0 Thank you for reading! About "How does js merge using nulls?? Operator "This article is shared here. I hope the above content can be of some help to everyone, so that everyone can learn more knowledge. If you think the article is good, you can share it and let more people see it!

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