map Size in TypeScript

In TypeScript, we can get the size of a hash using the Object.keys() method. This method returns an array of keys from the hash, which we can then call the length property on to get the size of the hash.

Here's an example:

const myHash = {
  name: 'John',
  age: 25,
  location: {
    city: 'New York',
    state: 'NY'
  }
};
const size = Object.keys(myHash).length;

console.log(size); // Outputs 3

In this example, we have a hash myHash with 3 keys and their respective values. We call Object.keys(myHash) to get an array of the keys in the hash. We then call length on this array to get the size of the hash, which is 3. We then log this value to the console.

Note that this method only gets the size of the hash's primary keys. If the values of the keys are also nested hashes or arrays, you would need to iterate through them and call Object.keys() on those as well to get their sizes.