How to get first N number of elements from an array

I am working with Javascript(ES6) /FaceBook react and trying to get the first 3 elements of an array that varies in size. I would like do the equivalent of Linq take(n).

In my Jsx file I have the following:

var items = list.map(i => {
  return (
    <myview item={i} key={i.id} />
  );
});

Then to get the first 3 items I tried

  var map = new Map(list);
    map.size = 3;
    var items = map(i => {
      return (<SpotlightLandingGlobalInboxItem item={i} key={i.id} />);
    });

This didn't work as map doesn't have a set function.

Can you please help?

To get the first n elements of an array, use

const slicedArray = array.slice(0, n);

I believe what you're looking for is:

// ...inside the render() function

var size = 3;
var items = list.slice(0, size).map(i => {
    return <myview item={i} key={i.id} />
}

return (
  <div>
    {items}
  </div>   
)

arr.length = n

This might be surprising but length property of an array is not only used to get number of array elements but it's also writable and can be used to set array's length MDN link. This will mutate the array.

If you don't care about immutability or don't want to allocate memory i.e. for a game this will be the fastest way.

to empty an array

arr.length = 0

You can filter using index of array.

var months = ['Jan', 'March', 'April', 'June'];
months = months.filter((month,idx) => idx < 2)
console.log(months);