jsThisNewDemo

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Study</title>
</head>
<body>
    <script>
// Closure version - https://pastebin.com/81212hiK

        `use strict`
        function Counter() {
            this.count = 0;
            this.set = function (val) { this.count = val; };
            this.get = function () { return this.count; };
            this.reset = function () { this.count = 0; };
            this.counter = function () { return this.count++; };
        }

        {
            let counterA = new Counter();
            counterA.set(26);
            for (let i = 0; i < 5; ++i) { console.log(`counterA.counter() - ${counterA.counter()}`) };
            console.log(`counterA.get() - ${counterA.get()}`);

            let counterB = new Counter()
            for (let i = 0; i < 5; ++i) { console.log(`counterB.counter() - ${counterB.counter()}`) };
            console.log(`counterB.get() - ${counterB.get()}`);

            counterA.reset();
            counterB.reset();
            console.log(`counterA.get() - ${counterA.get()}`);
            console.log(`counterB.get() - ${counterB.get()}`);
        }
    </script>
</body>
</html>