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30-seconds-of-code/snippets/isUndefined.md
2018-01-16 16:50:21 +02:00

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### isUndefined
Returns `true` if the specified value is `undefined`, `false` otherwise.
Use the strict equality operator to check if the value and of `val` are equal to `undefined`.
```js
const isUndefined = val => val === undefined;
```
```js
isUndefined(undefined); // true
```