JavaScript Functions — Function Definitions

In JavaScript functions can be declared in multiple ways, Let’s have a look

Anonymous Functions and Function Expressions

Function without a name are called anonymous functions.

JavaScript allows declaration of anonymous functions and function expression where functions are defined with expression.

//This is a anonymous function 
function (){

}

There is no way to call the above declared function.

To use an anonymous function we can declare the function using expression.

const addNumbers = function (num1,num2){
  return num1+num2;
}
console.log(addNumbers(2,3));

We will discuss more about function expression in call back functions.

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Arrow functions

Arrow Functions are introduced in ES6, arrow functions provides a concise syntax for writing function expressions.

const addNumbers =()=>{
return num1+num2;
}
console.log(addNumbers(2,3));

In the above example function key word is replaced with an arrow =>

IIFE (Immediately invoked function expression)

A function can call itself in JavaScript

(function (){

    console.log("Code Executed");

})();

When you execute the above code the anonymous function will execute automatically and print “Code Executed”.