Merge pull request #830 from liuhanqu/master

Another primitive assert function

snippets/isPrimitive.md

@@ -2,12 +2,10 @@
 
 Returns a boolean determining if the passed value is primitive or not.
 
-Use `Array.prototype.includes()` on an array of type strings which are not primitive,
-supplying the type using `typeof`.
-Since `typeof null` evaluates to `'object'`, it needs to be directly compared.
+Create an object from `val` and compare it with `val` to determine if the passed value is primitive (i.e. not equal to the created object).
 
 ```js
-const isPrimitive = val => !['object', 'function'].includes(typeof val) || val === null;
+const isPrimitive = val => Object(val) !== val;
 ```
 
 ```js