find the symmetric difference of two maps in javascript

One way to find the symmetric difference of two maps in JavaScript is to use the Set object and the spread operator. Here is an example implementation:

index.tsx
// Define two maps
const map1 = new Map([['a', 1], ['b', 2], ['c', 3]]);
const map2 = new Map([['b', 4], ['c', 3], ['d', 5]]);

// Get the keys of each map
const keys1 = new Set(map1.keys());
const keys2 = new Set(map2.keys());

// Get the symmetric difference of the keys
const symmetricDifference = new Set([...keys1].filter(key => !keys2.has(key)).concat([...keys2].filter(key => !keys1.has(key))));

// Create a new map with the symmetric difference
const result = new Map([...symmetricDifference].map(key => [key, map1.has(key) ? map1.get(key) : map2.get(key)]));

console.log(result); // Output: Map(3) { 'a' => 1, 'b' => 4, 'd' => 5 }
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In this implementation, we first create two maps map1 and map2. We then get the keys of each map using the keys method and create two Set objects keys1 and keys2.

To get the symmetric difference of the keys, we use the filter method and the has method of Set. We combine the results of the two filter calls using the concat method and create a new Set object symmetricDifference.

Finally, we create a new map result with the entries from map1 and map2 that correspond to the keys in symmetricDifference. We use the ternary operator to check if the key exists in map1 or map2 and get the corresponding value.

The output of this implementation is a new map with the entries from map1 and map2 that are not present in both maps.