Using the Set function to compare distinct elements within different arrays

Update: After reviewing the link shared by faintsignal, it appears to be the most suitable answer. It not only clarifies why this behavior is happening but also provides a solution to the issue at hand.

I am currently working with an array and trying to determine if all elements are equal to a single value. The code snippet below seems like it should accomplish this task, however, it is not producing the expected outcome. Can someone shed some light on this?


var array1 = ['foo', 'bar', 'baz'];
var array2 = ['foo', 'foo', 'foo'];

//I anticipate this to be false, which it is
new Set(array1) == new Set(['foo']);

//I anticipate this to be true, but it is not
new Set(array2) == new Set(['foo']);

Any insights or information regarding this matter would be greatly appreciated!

Answer №1

To determine if the set size is one, you can do the following:

new Set(array2).size === 1

It's worth noting that in this scenario,

new Set(array2) == new Set(['foo'])

This statement returns false because different objects are not considered equal. However, it is possible to compare new Set(array2) and new Set(['foo']) using methods mentioned in the comments section. Nevertheless, simply checking if the size is 1 accomplishes the same outcome without any extra steps.

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