find the difference of two maps in typescript

We can find the difference between two maps in TypeScript by first creating a new map object and then iterating over the keys of the two maps using the spread operator to create new objects with the respective values for each key. We can then use the reduce method to compare the values of the two objects and return a new object with the differences.

Here's an example code snippet that shows how to do this:

index.ts
const map1 = new Map([
  ['a', 1],
  ['b', 2],
  ['c', 3],
]);

const map2 = new Map([
  ['a', 1],
  ['b', 4],
  ['d', 5],
]);

const difference = [...map1.keys(), ...map2.keys()].reduce((acc, key) => {
  if (map1.get(key) !== map2.get(key)) {
    acc.set(key, [map1.get(key), map2.get(key)]);
  }
  return acc;
}, new Map());

console.log(difference); // Output: Map(2) { 'b' => [ 2, 4 ], 'd' => [ undefined, 5 ] }
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In this example, map1 and map2 are the two maps we want to compare. We first get all the keys from both maps using the spread operator and iterate over them using the reduce method. For each key, we check if the values in the two maps are the same or not. If they are different, we store them in the acc object along with the key as a tuple. Finally, we return the new Map object with the differences.