I'm looking for a function to select the objects that are repeated in all subarrays from the main array

array = [
  [{"post_id": 86403},{"post_id": 86404},{"post_id": 86405}],
  [{"post_id": 86403},{"post_id": 86404},{"post_id": 86407}],
  [{"post_id": 86403},{"post_id": 86404},{"post_id": 86409}]
];

I expect it return {"post_id": 86403} and {"post_id": 86404} that are repeated in every subarray

I found this but it's not dynamic and the arrays must be entered manually also it has string like "Lorem" instead of object like {"post_id": 86403}

var array1 = ["Lorem", "ipsum", "dolor"],
    array2 = ["Lorem", "ipsum", "quick", "brown", "foo"],
    array3 = ["Jumps", "Over", "Lazy", "Lorem"],
    array4 = [1337, 420, 666, "Lorem"],
    data = [array1, array2, array3, array4],
    result = data.reduce((a, b) => a.filter(c => b.includes(c)));

console.log(result);

CodePudding user response：

You can use the same pattern as in the solution you found: it is a matter of matching post_id properties instead of the array values themselves:

• The filter callback should retrieve the post_id from the iterated item
• The includes call should be replaced with some, whose callback will grab the other post_id and compare it

var data = [
  [{"post_id": 86403},{"post_id": 86404},{"post_id": 86405}],
  [{"post_id": 86403},{"post_id": 86404},{"post_id": 86407}],
  [{"post_id": 86403},{"post_id": 86404},{"post_id": 86409}]
];
var result = data.reduce((a, b) => 
   a.filter(({post_id: c}) => b.some(({post_id}) => post_id == c))
);

console.log(result);