unique array javascript map code example

Example 1: unique array javascript es6 Map

const data = [
  { group: 'A', name: 'SD' }, 
  { group: 'B', name: 'FI' }, 
  { group: 'A', name: 'MM' },
  { group: 'B', name: 'CO'}
];
const unique = [...new Set(data.map(item => item.group))]; // [ 'A', 'B']

Example 2: javascript get distinct values from array

const categories = ['General', 'Exotic', 'Extreme', 'Extreme', 'General' ,'Water', 'Extreme']
.filter((value, index, categoryArray) => categoryArray.indexOf(value) === index);

This will return an array that has the unique category names
['General', 'Exotic', 'Extreme', 'Water']