Javascript Higher Order Functions

In this tutorial, we will learn about Higher order functions in Javascript:

Higher Order Functions:

• Higher-order function is a function that takes one or more functions as arguments and/or returns a function
• Higher order functions allow for writing more abstract and reusable code
• Higher-order functions are widely used in functional programming and can be used to perform common operations such as filtering, mapping, and reducing arrays.
• They also allow for a more flexible and composable codebase.

Higher Order Function Example :

function display(func) {
  func();
  func();
}

function logToConsole() {
  console.log("Hello!");
}

callTwice(logToConsole);

• In this example, the display function is a higher-order function that takes a func argument, which is a function
• The display function calls the func argument twice.
• The logToConsole function is defined and passed as an argument to display , so it is executed twice when display is called.

Higher Order Function Real time Examples:

In this example, it takes an array and a callback function as arguments and returns the first element in the array that satisfies the condition specified by the callback:

function findElement(array, callback) {
  for (let i = 0; i < array.length; i++) {
    if (callback(array[i])) {
      return array[i];
    }
  }
  return undefined;
}

const numbers = [1, 2, 3, 4, 5];

const firstEvenNumber = findElement(numbers, function(number) {
  return number % 2 === 0;
});

console.log(firstEvenNumber); // 2

In this example, the findElement function takes an array and a callback function as arguments. The findElement function loops over the elements in the array and calls the callback function with each element. If the callback function returns true, the element is returned. If the loop finishes and no elements satisfy the condition, undefined is returned.

The firstEvenNumber constant is defined by calling findElement with the numbers array and a callback function that checks if the number is even. The result is logged to the console, which is 2.

Thanks for Reading..