# What does this destructuring default print?

**URL:** <https://forum.kirupa.com/t/what-does-this-destructuring-default-print/679717>\
**Category:** web dev\
**Created:** [March 30, 2026, 6:00pm UTC](https://forum.kirupa.com/t/what-does-this-destructuring-default-print/679717 "2026-03-30T18:00:06Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Ellen1979](https://yyz1.discourse-cdn.com/flex011/user_avatar/forum.kirupa.com/ellen1979/32/31260_2.png) [@Ellen1979](https://forum.kirupa.com/u/Ellen1979)\
**Post date:** [March 30, 2026, 6:00pm UTC](https://forum.kirupa.com/t/what-does-this-destructuring-default-print/679717/1 "2026-03-30T18:00:07Z")

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Simple JavaScript output question.

```javascript
const { a = 5 } = { a: undefined };
console.log(a);

```

What is the output and why.

Ellen 😊

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<div class="post-metadata">

**Author:** ![Yoshiii](https://yyz1.discourse-cdn.com/flex011/user_avatar/forum.kirupa.com/yoshiii/32/31156_2.png) [@Yoshiii](https://forum.kirupa.com/u/Yoshiii)\
**Post date:** [March 30, 2026, 6:14pm UTC](https://forum.kirupa.com/t/what-does-this-destructuring-default-print/679717/2 "2026-03-30T18:14:04Z")

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It prints `5`, because destructuring defaults kick in when the property value is `undefined`-if it were `null`, you’d get `null` instead.

Yoshiii