JSFiddle - React, Tailwind, and code Playground
JavaScript
class Unique {
constructor(items) {
this.items = items;
}
append(newItems) {
newItems.forEach((newItem) => {
if (!this.items.includes(newItem)) {
this.items.push(newItem);
}
});
}
}
const uniqueColors = new Unique(['blue']);
console.log(uniqueColors.items); // => ['blue']
uniqueColors.append(['red', 'blue']);
console.log(uniqueColors.items); // => ['blue', 'red']