javascript to remove duplicates from an array code example

Example 1: js delete duplicates from array

const names = ['John', 'Paul', 'George', 'Ringo', 'John'];

let unique = [...new Set(names)];
console.log(unique); // 'John', 'Paul', 'George', 'Ringo'

Example 2: javascript to remove duplicates from an array

uniqueArray = a.filter(function(item, pos) {
    return a.indexOf(item) == pos; 
})

Example 3: javascript remove duplicates from array

unique = [...new Set(arr)];   // where arr contains duplicate elements

Example 4: javascript to remove duplicates from an array

uniqueArray = a.filter(function(item, pos) {
    return a.indexOf(item) == pos;
})

Example 5: remove duplicates from array javascript

arr.filter((v,i,a)=>a.findIndex(t=>(t.place === v.place && t.name===v.name))===i)

Example 6: remove duplicate array es6

let a = [10,20,30,50,30];
let b = a.reduce((unique,item) => unique.includes(item) ? unique: [... unique, item] ,[]); 
console.log(b);