399 B
399 B
title, tags
| title | tags |
|---|---|
| head | array,beginner |
Returns the head of an array.
- Check if
arris truthy and has alengthproperty. - Use
arr[0]if possible to return the first element, otherwise returnundefined.
const head = arr => (arr && arr.length ? arr[0] : undefined);
head([1, 2, 3]); // 1
head([]); // undefined
head(null); // undefined
head(undefined); // undefined