When working in TypeScript, there are two different ways to declare a map. The first way is like this:
{[key:number]string}
This shows an example of creating a map with keys as numbers and values as strings. However, you can also define a map like this:
Map<number, string>
What is the reason for having these two methods to achieve the same result, and what are the differences between them?
A Map is a built-in JavaScript object that stores pairs of keys and values. For example:
let myMap = new Map();
myMap.set('key1','value1');
myMap.set('key2','value2');
By doing this, you create a map containing those key-value pairs.
In contrast, the type {[key:number]: string} represents an object with keys of type number and values of type string. The key difference between a map and a regular object is that a map allows keys of any type (not limited to just strings, numbers, or Symbols like objects) and is also more optimized. Check out the MDN documentation for a detailed comparison between objects and maps.
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