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snippets/js/s/is-undefined.md

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