class Person {

    constructor(firstName, lastName) {

        this.firstName = firstName;

        this.lastName = lastName;

    }

    get fullName() {

        return `${this.firstName} ${this.lastName}`;

    }

};

​

let args = ['John', 'Doe'];

​

let john = Reflect.construct(

    Person,

    args

);

​

console.log(john instanceof Person);

console.log(john.fullName); // John Doe

Code language: JavaScript (javascript)