JAVASCRIPT

javascript arrow function

// Non Arrow (standard way)
let add = function(x,y) {
  return x + y;
}
console.log(add(10,20)); // 30

// Arrow style
let add = (x,y) => x + y;
console.log(add(10,20)); // 30;

// You can still encapsulate
let add = (x, y) => { return x + y; };

Arrow Functions

// The usual way of writing function
const magic = function() {
  return new Date();
};

// Arrow function syntax is used to rewrite the function
const magic = () => {
  return new Date();
};
//or
const magic = () => new Date();

name arrow function

//Long version  
function add(a, b) {  
    return a + b;   
}

// Shorthand  
const add = (a, b) => a + b;   

how to write an arrow function in javascript?

function double(x) { return x * 2; } // Traditional way
console.log(double(2)) // 4


const double = x => x * 2; // Same function written as an arrow function with implicit return
console.log(double(2)) // 4

arrow functions=>

// Traditional Anonymous Function
function (a, b){
  return a + b + 100;
}

// Arrow Function
(a, b) => a + b + 100;

// Traditional Anonymous Function (no arguments)
let a = 4;
let b = 2;
function (){
  return a + b + 100;
}

// Arrow Function (no arguments)
let a = 4;
let b = 2;
() => a + b + 100;

arrow function

const doSomething = () => {
  // Function Scope
};

An Arrow Function

/*The arrow functions were introduced in ECMA 2015 with the main purpose of giving a shorter syntax to a function expression. 
Besides providing shorter syntax, which increases the readability of the code, 
it does not have its own value of the this object. The value of this object inside an arrow function is inherited from the enclosing scope.

You can write an arrow function to add two numbers as shown in the next code example.*/

var add = (num1, num2)=> num1+num2; 
let res = add(5,2);
console.log(res); // 7 

javascript arrow function

const welcome = () => {
	console.log("THIS IS A ARROW FUNCTION")
}

Javascript basic arrow function

const power = (base, exponent) => {
    let result = 1;
    for (let count = 0; count < exponent; count++) {
      result *= base;
    }
    return result;
  };

arrow function

const = newfunc =(a,b)=>{
	return a+b
}

shorthand arrow function

const = newfunc = (a,b)=> a+b

Arrow Function Example

let nums = [3, 5, 7]
let squares = nums.map(function (n) {
  return n * n
})
console.log(squares)

arrow function

const hello = () => {  
 return 'Hello'
}

const hello = () => 'Hello'
console.log(hello())

arrow functions

let add = (x, y) => x + y;

console.log(add(10, 20)); // 30;
Code language: JavaScript (javascript)

JavaScript Arrow Function

// function expression
let x = function(x, y) {
   return x * y;
}

arrow functions=>

(param1, paramN) => {
   let a = 1;
   return a + param1 + paramN;
}

arrow function

const bk = () =>{
   console.log("Bk function called");
}
bk()

arrow functions=>

// Traditional Anonymous Function
function (a, b){
  let chuck = 42;
  return a + b + chuck;
}

// Arrow Function
(a, b) => {
  let chuck = 42;
  return a + b + chuck;
}

arrow function

textBox.addEventListener('keydown', (event) => {
  console.log(`You pressed "${event.key}".`);
});

javascript Arrow Function Syntax

let myFunction = (arg1, arg2, ...argN) => {
    statement(s)
}

Arrow Function Example

let nums = [3, 5, 7]
let squares = nums.map((n) => {
  return n * n
})
console.log(squares)

arrow function

// Traditional Function
function (a){
  return a + 100;
}

// Arrow Function Break Down

// 1. Remove the word "function" and place arrow between the argument and opening body bracket
(a) => {
  return a + 100;
}

// 2. Remove the body brackets and word "return" -- the return is implied.
(a) => a + 100;

// 3. Remove the argument parentheses
a => a + 100;

arrow function

// Arrow function with two arguments const sum = (firstParam, secondParam) => {   return firstParam + secondParam; }; console.log(sum(2,5)); // Prints: 7  // Arrow function with no arguments const printHello = () => {   console.log('hello'); }; printHello(); // Prints: hello // Arrow functions with a single argument const checkWeight = weight => {   console.log(`Baggage weight : ${weight} kilograms.`); }; checkWeight(25); // Prints: Baggage weight : 25 kilograms.  // Concise arrow functionsconst multiply = (a, b) => a * b; console.log(multiply(2, 30)); // Prints: 60 

arrow function Java Script

param => expression
(param) => expression

// Arrow Function
(a, b) => {
  const chuck = 42;
  return a + b + chuck;
};

Arrow functions syntax

const introduction = () => {
    console.log("Hello, my name is Jessica.");
};