JavaScript(JS) JS pass a function as parameter

In JavaScript, you can pass a function as a parameter to another function. This is a common pattern used in functional programming and can be very useful for creating more modular and reusable code.

Here is an example of how to pass a function as a parameter:

// Define a function that takes a callback function as a parameter
function doSomething(callback) {
  console.log('Doing something...');
  // Call the callback function
  callback();
}

// Define a function that will be used as the callback
function afterSomething() {
  console.log('Done doing something.');
}

// Call the doSomething function and pass the afterSomething function as the callback
doSomething(afterSomething);

In this example, the doSomething function takes a single parameter called callback, which is a function. Inside the doSomething function, it calls the callback function.

The afterSomething function is defined separately and will be passed as the callback function to the doSomething function when it is called.

When you run this code, you should see the following output in the console:

Doing something...
Done doing something.

This is just a simple example, but you can use this pattern to pass any function as a parameter to another function, allowing you to create more flexible and reusable code.