What is the best way to do the below in more functional way (with ES6/ES7)

let cols = [];

for (let i =0; i <= 7; i++) {

   cols.push(i * i);

}

return cols;

I tried like,

return [ ...7 ].map(i => {

  return i * i;

});

but that translated to

[].concat(7).map(function (n) {

  return n * n;

});

which is not what I expected.

EDIT:

@pavlo. Indeed, that was a mistake. I was using JSX, and for example, I want 7 divs, (untested)

let cols = [];

    for (let i =0; i <= 7; i++) {

       cols.push(<div id={i}> ...  </div>)

    }

    return cols;

so the idea was indeed to reduce the number of temp variables and procedural feel.