toType
A better alternative to the typeof-operator in JS. Utilizes the internal [[CLASS]] property.
The function toType is designed as an alternative to the built in typeof operator and takes one argument and returns a string. It utilizes the internal [[CLASS]] property of Javascript Objects. See the following code for comparison:
typeof undefined; //"undefined"
typeof null; //"object"
typeof true; //"boolean"
typeof 123; //"number"
typeof "Hello World!"; //"string"
typeof {a: 4}; //"object"
typeof [1, 2, 3]; //"object"
(() => {console.log(typeof arguments)})(); //"object"
typeof new ReferenceError; //"object"
typeof new Date; //"object"
typeof /a-z/; //"object"
typeof Math; //"object"
typeof JSON; //"object"
typeof new Boolean(true); //"object"
typeof new Number(4); //"object"
typeof new String("abc"); //"object"toType(undefined); //"undefined"
toType(null); //"null"
toType(true); //"boolean"
toType(123); //"number"
toType("Hello World!"); //"string"
toType({a: 4}); //"object"
toType([1, 2, 3]); //"array"
(() => {console.log(toType(arguments))})(); //"arguments"
toType(new ReferenceError); //"error"
toType(new Date); //"date"
toType(/a-z/); //"regexp"
toType(Math); //"math"
toType(JSON); //"json"
toType(new Boolean(true)); //"boolean"
toType(new Number(4)); //"number"
toType(new String("abc")); //"string"As you can see, there is a vast difference between the built-in typeof operator and the new toType function when it comes to more specific type checking, like regular expressions, built-in objects, error objects or even arrays.