How to check array in array with "Underscore"?

I would like to check array in array with underscore

var a = [1, 2, 3];
var b= [1, 2, 3, 4, 5]

check a in b // true

Please help me.

Would Lodash Difference work for you?

If array B is the one you compare everything at, you could check the difference between A and B and deduce from that if array A is in (or partially in) B.

Lodash is an extention of underscore, package you can use is:
meteor add stevezhu:lodash

Don’t forget to initiate lodash in your Lib folder like:

@_ = lodash

If you don’t do that, the _ namespace will be still assigned to Underscore and not Lodash

Alternative solution would be to use and loop through B and check during each iteration if the value of the current B array element is part of array A (using IndexOf or something)

Hi, may be :

(_.size(_.difference(a,b)) == 0) ? true : false;
var aIsInB = !_.difference(a, b).length;

I use sugar.js for that

You’d simply do an intersect of a and b and compare the result to a.

Look great for Sugar JS.
I missing before…


[1,3,5].intersect([5,7,9]) => [5]


_.intersection([1,3,5],[5,7,9]) => [5]