function isObject(obj) {
        // The method can't do a type cast since there are type (like strings) which
        // are subclasses of any put not positvely matched by the function. Hence type
        // narrowing results in wrong results.
        return typeof obj === _typeof.object
            && obj !== null
            && !Array.isArray(obj)
            && !(obj instanceof RegExp)
            && !(obj instanceof Date);
    }
@returns whether the provided parameter is of type `object` but **not**
	`null`, an `array`, a `regexp`, nor a `date`.