Underscore.JS - findLastIndex method

Syntax

_.findLastIndex(array, predicate, [context])

findLastIndex method return the last index of element in array using predicate function applied on each element.

Example

var _ = require('underscore');

var list = [1, 2, 4, 5, 6]
//Example: get index of last even number
result = _.findLastIndex(list, function(x){ return x % 2 == 0} );
console.log(result)

list = [{name: 'Joe', age: 40}, {name: 'Rob', age: 60},, {name: 'Julie', age: 60}];
//Example: get index of employee of age: 60
result = _.findLastIndex(list, function(x){ return x.age == 60} );
console.log(result)

Save the above program in tester.js. Run the following command to execute this program.

Command

\>node tester.js

Output

4
3