class Namaku {
    #firstname;
    #lastname;

    set firstName(fname) {
        this.#firstname = fname;
    }
    set lastName(lname) {
        this.#lastname = lname;
    }

    get sapaSaya() {
        return `Halo ${this.#firstname} ${this.#lastname} .... selamat malam!`;
    }
}
const iwan = new Namaku();

iwan.firstName = "Muhammad";
iwan.lastName = "Ridwan";

iwan.#firstname = "Beddu";
iwan.#lastname = "O'Conners";

console.log(iwan.sapaSaya); 
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