Filter arrays for unique objects

Get only unique objects in an array or between two arrays

var arr = [
  {email: 'matthew@gmail.com', id: 10}
]

var arr2 = [
  {email: 'matthew@gmail.com', id: 10},
  {email: 'matthew@gmail.com', id: 13}
]

var mergedArray = arr.concat(arr2);
var map         = new Map(mergedArray.map(o => [o.id,o]));
var unique      = [...map.values()];

console.log(unique);
// returns [{email:  "matthew@gmail.com",  id:  10},{email:  "matthew@gmail.com" id:  13}]