The JavaScript Set object is a feature supported by ES6. The set object can store any value, whether primitive or objects. No value is returned to the Set property. If you've added an element of the same value, it won't add.
JavaScript Set
JavaScript Setter
The setters are functions or methods used to assign variables. The setter concept is common in computer programming: almost all high-end programming languages, including JS, come with a syntax for the setter.
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