21 lines
363 B
Markdown
21 lines
363 B
Markdown
---
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title: Value is undefined
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type: snippet
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language: javascript
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tags: [type]
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cover: peaches
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dateModified: 2020-10-20T23:02:01+03:00
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---
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Checks if the specified value is `undefined`.
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- Use the strict equality operator to check if `val` is equal to `undefined`.
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```js
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const isUndefined = val => val === undefined;
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```
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```js
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isUndefined(undefined); // true
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```
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