Classes

class is cleaner syntax for constructor functions and prototypes. Under the hood, JS is still prototype-based.

• constructor runs on new.
• methods live on the prototype.
• extends creates a subclass.

class Counter {
  constructor() {
    this.n = 0;
  }
  inc() {
    this.n += 1;
    return this.n;
  }
}
console.log(new Counter().inc());

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