seysdev

<button class="one">18</button>
<button class="two">22</button>

<div id="changes">
</div>

seysdev

function factorial( n ) {
  if ( n === 1 ) {
    return 1;
  }
  return n * factorial( n - 1 );
}

factorial(6) // 720

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// example 1 // simple composition
function concatName(firstname, lastname) {
 return `${firstname} ${lastname}`;
}

function injetDom(element) {
 document.querySelector('body').innerHTML = element;
}

injectDom(concatName('sebastian', 'yabiku'))

seysdev

// inmmutability 
const resultAccounts = ['12367', '12368', '22367', '22368', '32367', '32368'];

function AccountsByNumberInit(account, number) {
 return account.substring(0,1) === number
}

const accountsStartOne = resultAccounts.filter(account => AccountsByNumberInit(account, '1'));
const accountsStartTwo = resultAccounts.filter(account => AccountsByNumberInit(account, '2'));
const accountsStartThree = resultAccounts.filter(account => AccountsByNumberInit(account, '3'));

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let numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];

// filter
let filterNumber = numbers.filter((number) => number > 5) // 6, 7, 8, 9, 10

// reduce
let reduceNumber = numbers.reduce((previousNumber, currentNumber) => previousNumber + currentNumber); // 10

// reduce initial 
let reduceInitial = numbers.reduce((previousNumber, currentNumber) => previousNumber + currentNumber, 10); // 20

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// assign to variables
const f = (m) => console.log(m)
f('Test')

// assing in objet
const obj = {
  f(m) {
    console.log(m)
  }
}

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// function pure
function add(x) {
 return x + 2;
}

// function not pure
let y = 2;
function add2(x) {
  return x + y;
}

seysdev

let animals = [
  {
    name: 'Rin tin tin',
    species: 'dog'
  },
  {
    name: 'gardfield',
    species: 'cat'
  },
  {

seysdev

// prototype heritage
function Animal(type, species){
 this.type = type;
 this.species = species;
}

Animal.prototype.say = function() {
 return `The ${this.type} is a ${this.species} and say ${say}`;
}

seysdev

let numbers = [12, 32, 45, 13, 19];
let add = 0;
let average = 0;
  
for (let i= 0; i < marks.length; i++) {
  add += marks[i]; 
}

average = add / marks.length;