When to use const with objects in JavaScript? : <p>I recently read about ES6 <code>const</code> keyword and I can understand its importance when having something like this:</p>

<pre><code>(function(){
    const PI = 3.14;
    PI = 3.15; //  Uncaught TypeError: Assignment to constant variable
})();
</code></pre>

<p>So, nobody can change my <code>PI</code> variable.</p>

<p>The misunderstanding I have is that I don't understand in which situation the use of <code>const</code> with objects can make sense (other than preventing people to do <code>myObj = newValue;</code>).</p>

<pre><code>(function(){
    const obj = {a:1 ,b: 2, c:3};
    //obj = {x:7 , y:8, z: 9}
    //This is good
    //TypeError: Assignment to constant variable.

    obj.a=7; obj.b=8 ; obj.c=9;
    console.log(obj); //outputs: {a: 7, b: 8, c: 9}
})();
</code></pre>

<p>So when declaring an object: when should I say: Now I <strong>must</strong> declare my object with <code>const</code>?</p>
