Kebab file names

snippets/is-promise-like.md

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+---
+title: Value is promise-like
+tags: type,function,promise
+cover: digital-nomad-13
+firstSeen: 2017-12-31T14:25:43+02:00
+lastUpdated: 2020-10-20T23:02:01+03:00
+---
+
+Checks if an object looks like a [`Promise`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise).
+
+- Check if the object is not `null`, its `typeof` matches either `object` or `function` and if it has a `.then` property, which is also a `function`.
+
+```js
+const isPromiseLike = obj =>
+  obj !== null &&
+  (typeof obj === 'object' || typeof obj === 'function') &&
+  typeof obj.then === 'function';
+```
+
+```js
+isPromiseLike({
+  then: function() {
+    return '';
+  }
+}); // true
+isPromiseLike(null); // false
+isPromiseLike({}); // false
+```