Get type of a variable in string

JavaScript

const getTypeOf = (obj) => Object.prototype.toString.call(obj).match(/\[object (.*)\]/)[1]

TypeScript

const getTypeOf = (obj: any): string => (Object.prototype.toString.call(obj).match(/\[object (.*)\]/) as string[])[1]

Examples

getTypeOf('hello world') // String
getTypeOf(1000) // Number
getTypeOf(Infinity) // Number
getTypeOf(true) // Boolean
getTypeOf(Symbol()) // Symbol
getTypeOf(null) // Null
getTypeOf(undefined) // Undefined
getTypeOf({}) // Object
getTypeOf([]) // Array
getTypeOf(/[a-z]/g) // RegExp
getTypeOf(new Date(2021)) // Date
getTypeOf(new Error()) // Error
getTypeOf(function () {}) // Function
getTypeOf((a, b) => a + b) // Function
getTypeOf(async () => {}) // AsyncFunction
getTypeOf(document) // HTMLDocument