Arrays

Arrays

Credits: illustration by unDraw‚Äč

1. What's Array(k) really doing?

Example:

```js var a = Array( 3 ); a; // [] a[2]; // undefined a.length; // 3 a.map( (v,idx)=>idx ); // [ ]

var b = Array.apply( null, Array(3) ); b; // [undefined,undefined,undefined] b[2]; // undefined b.length; // 3 b.map( (v,idx)=>idx ); // [0,1,2]

```

TODO: explanation