Rename js snippets

snippets/js/s/last-array-element.md

@@ -0,0 +1,24 @@
+---
+title: Last array element
+type: snippet
+language: javascript
+tags: [array]
+cover: white-laptop
+dateModified: 2020-10-20T23:02:01+03:00
+---
+
+Returns the last element in an array.
+
+- Check if `arr` is truthy and has a `length` property.
+- Use `Array.prototype.length` to compute the index of the last element of the given array and return it, otherwise return `undefined`.
+
+```js
+const last = arr => (arr && arr.length ? arr[arr.length - 1] : undefined);
+```
+
+```js
+last([1, 2, 3]); // 3
+last([]); // undefined
+last(null); // undefined
+last(undefined); // undefined
+```