Rename js snippets

snippets/js/s/all-array-elements-are-falsy.md

@@ -0,0 +1,22 @@
+---
+title: Test if all array elements are falsy
+type: snippet
+language: javascript
+tags: [array]
+cover: little-white-flowers
+dateModified: 2020-10-21T21:54:53+03:00
+---
+
+Checks if the provided predicate function returns `false` for all elements in a collection.
+
+- Use `Array.prototype.some()` to test if any elements in the collection return `true` based on `fn`.
+- Omit the second argument, `fn`, to use `Boolean` as a default.
+
+```js
+const none = (arr, fn = Boolean) => !arr.some(fn);
+```
+
+```js
+none([0, 1, 3, 0], x => x == 2); // true
+none([0, 0, 0]); // true
+```