What do you make of this?

```
var x = {a: 1};         //=> {a: 1}
var y = Object.keys(x); //=> ['a']
x[y]                    //=> 1

```

if `y = ['a']`, `x[y]` is the same as doing `x[['a']]`, right?

```
x[['a']];               //=> 1

x[[['a']]];             //=> 1

x[[[[[[[['a']]]]]]]];   //=> 1

```

Can someone explain what's happening here? Why does this work?