How to Use Symbols in JavaScript?

In JavaScript, a symbol is a unique and immutable data type that can be used as an object property or object key. Symbols are a great way to define hidden properties that cannot be accidentally overridden or accessed by other code.

Here’s how you can use symbols in JavaScript:

1. Creating a Symbol: To create a symbol, you can use the Symbol() function. You can also provide a description for the symbol as an argument, but this is optional.

const mySymbol = Symbol();
const myDescribedSymbol = Symbol('My Described Symbol');

2. Using Symbols as Object Properties: You can use symbols as object properties just like you would use any other property. The difference is that symbols are unique, so you won’t have to worry about name collisions.

const myObject = {};
myObject[mySymbol] = 'My Symbol Property';
console.log(myObject[mySymbol]); // Output: My Symbol Property

3. Using Symbols as Object Keys: You can also use symbols as object keys to define properties with unique names. This can be useful when you want to define hidden properties that should not be accessed by other code.

const myObject = {
  [mySymbol]: 'My Symbol Key'
};
console.log(myObject[mySymbol]); // Output: My Symbol Key

4. Global Registry: If you want to create a symbol that can be easily shared across multiple parts of your code, you can use the global symbol registry. You can access the registry using the Symbol.for() method and pass a string that represents the symbol.

const myGlobalSymbol = Symbol.for('My Global Symbol');
const myObject = {
  [myGlobalSymbol]: 'My Global Symbol Key'
};
console.log(myObject[myGlobalSymbol]); // Output: My Global Symbol Key

These are just a few examples of how you can use symbols in JavaScript. By using symbols, you can define hidden properties that cannot be accidentally overridden or accessed by other code, making your code more robust and maintainable.