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Javascript Removing duplicate elements

you can use the native method Array.prototype.filter to loop through an array and leave only entries that pass a given callback function.
In the following example, our callback checks if the given value occurs in the array. If it does, it is a duplicate and will not be copied to the resulting array.

var uniqueArray = ['a', 1, 'a', 2, '1', 1].filter(function(value, index, self) {
 return self.indexOf(value) === index;


['a', 1, 2, '1']

you can also use the Set object. This object lets you store unique values of any type, whether primitive values or object references:

var uniqueArray = ['q', 2, 'b', 2, 'r', 3].filter(function(value, index, self) {
 return self.indexOf(value) === index;


['q', 2, 'b', '2', 'r']


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