class Car {
constructor(model, year, miles) {
this.model = model;
this.year = year;
this.miles = miles;
}
toString() {
return `${this.model} has done ${this.miles} miles`;
}
}
↓
class Car {
constructor(model, year, miles) {
this.model = model;
this.year = year;
this.miles = miles;
}
}
Car.prototype.toString = function() {
return `${this.model} has done ${this.miles} miles`;
}
};
// ↑すべてのインスタンスで toString を共有するようになる。