I'm using the lodash includes function to check if a target value exists in an array...

_.includes(array, target) 

and was hoping to find a good equivalent in ES5 (or ES6)

Did I miss something? Is there no ES5 Array.prototype equivalent?

Or is my only option to use indexOf?

I'm using the lodash includes function to check if a target value exists in an array...

_.includes(array, target) 

and was hoping to find a good equivalent in ES5 (or ES6)

Did I miss something? Is there no ES5 Array.prototype equivalent?

Or is my only option to use indexOf?

• javascript
• arrays
• lodash

• 1 As you surmise, your best option in vanilla ES5 is .indexOf() as in array.indexOf(target) !== -1. – jfriend00 Commented Jul 17, 2015 at 0:06
• There is also Array.prototype.some if you want something a bit smarter than indexOf (also see MDN), so array.some(function(o){return o === target}). – RobG Commented Jul 17, 2015 at 0:27
• Just out of curiosity, what's wrong with lodash includes()? – Adam Boduch Commented Jul 17, 2015 at 18:37
• 1 @AdamBoduch - No plaints about lodash. I love lodash. Just exploring the pain point for removing the dependency. – sfletche Commented Jul 17, 2015 at 18:52

1 Answer 1

ES2016: Array.prototype.includes()

[1, 2, 3].includes(2);     // true

ES5: Array.prototype.indexOf() >= 0

[2, 5, 9].indexOf(5) >= 0;   // true
[2, 5, 9].indexOf(7) >= 0;   // false

If you prefer a function:

function includes (array, element) { return array.indexOf(element) >= 0 }

and use it as:

includes([2, 5, 9], 5);    // true