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_posts/en/javascript/2020-11-04-what-is-a-void-operator.md

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+---
+layout: post
+
+title: What is a void operator?
+tip-number: 79
+tip-username: loverajoel
+tip-username-profile: https://www.twitter.com/loverajoel
+tip-tldr: The void operator returns an undefined value from an evaluated expression
+
+categories:
+    - en
+    - javascript
+---
+The `void` operator returns an `undefined` value from an evaluated expression, or in other words; the `void` operator specifies an expression to be evaluated without returning a value. It is commonly used in client-side JavaScript, where the browser should not display the value.
+
+```js
+function getYear() {
+  return 2020;
+};
+
+console.log(getYear());
+// Output: 2020
+
+console.log(void getYear());
+// Output: undefined
+
+// Useful use case
+button.onclick = () => void getYear();
+```