dottedsquirrel

let animals = [
    {name: 'Tibbers', type: 'cat', isNeutered: true, age: 2},
    {name: 'Fluffball', type: 'rabbit', isNeutered: false, age: 1},
    {name: 'Strawhat', type: 'cat', isNeutered: true, age: 5}
  ]

let allNeutered = animals.every(animal => {return animal.isNeutered});

//will return false because not all values under isNeutered evaluates to true

dottedsquirrel

let animals = [
    {name: 'Tibbers', type: 'cat', isNeutered: true, age: 2},
    {name: 'Fluffball', type: 'rabbit', isNeutered: false, age: 1},
    {name: 'Strawhat', type: 'cat', isNeutered: true, age: 5}
  ]

 /*using functional filter() where a represents an item in the array*/
 let neuteredAnimals = animals.filter((a) => {
     return a.isNeutered;
 });

dottedsquirrel

let animals = [
   {name: 'Tibbers', type: 'cat', isNeutered: true, age: 2},
   {name: 'Fluffball', type: 'rabbit', isNeutered: false, age: 1},
   {name: 'Strawhat', type: 'cat', isNeutered: true, age: 5}
 ]

 /*using imperative*/
 let neuteredAnimals = [];

for (let i=0; i < animals.length; i++){

dottedsquirrel

let animals = [
    {name: 'Tibbers', type: 'cat', isNeutered: true, age: 2},
    {name: 'Fluffball', type: 'rabbit', isNeutered: false, age: 1},
    {name: 'Strawhat', type: 'cat', isNeutered: true, age: 5}
  ]

animalTypeFound = animals.find( animal => animal.type === 'cat' );

// animalTypeFound will return:
// {name: 'Tibbers', type: 'cat', isNeutered: true, age: 2}

dottedsquirrel

let animals = [
    {name: 'Tibbers', type: 'cat', isNeutered: true, age: 2},
    {name: 'Fluffball', type: 'rabbit', isNeutered: false, age: 1},
    {name: 'Strawhat', type: 'cat', isNeutered: true, age: 5}
  ]

// what you need: 
// ['Tibbers', 'Fluffball', 'Strawhat']

let animalNames = animals.map(animal => {return animal.name});

dottedsquirrel

let numbers = [100, 20, 10];

// result will return 70 as the value
// The function inside reduce will run twice. 
// the first time, x = 100, y = 20
// the second time, x = 80, y = 10

result = numbers.reduce((x, y) => { return x - y; });

dottedsquirrel

let animals = [
    {name: 'Tibbers', type: 'cat', isNeutered: true, age: 2},
    {name: 'Fluffball', type: 'rabbit', isNeutered: false, age: 1},
    {name: 'Strawhat', type: 'cat', isNeutered: true, age: 5}
  ]

// How old are all the animals combined?
// 0 is the starting value and acts as the first acculmulator value
// will return 8

dottedsquirrel

let animals = [
    {name: 'Tibbers', type: 'cat', isNeutered: true, age: 2},
    {name: 'Fluffball', type: 'rabbit', isNeutered: false, age: 1},
    {name: 'Strawhat', type: 'cat', isNeutered: true, age: 5}
  ]

let someAreCats = animals.some(animal => {return animal.type === 'cat'});

// will return true because at least one animal.type returned 'cat'

dottedsquirrel

let animals = [
    {name: 'Tibbers', type: 'cat', isNeutered: true, age: 2, enteredPagent: true, cutenessScore: 347},
    {name: 'Fluffball', type: 'rabbit', isNeutered: false, age: 1, enteredPagent: true, cutenessScore: 193},
    {name: 'Strawhat', type: 'cat', isNeutered: true, age: 5, enteredPagent: false, cutenessScore: 521}
  ]

//lets say you want to find the total cuteness score of all valid pagent entrants

let totalScore = animals
                    .filter(animal => {return animal.isNeutered})

dottedsquirrel

<div class="feedSection col l12 s12" *ngFor="let item of feed">
  <h3>{{item.details.publication}}</h3>
    <div class="featured col l6 s12">
      <p class="date">{{item.items[0].pubDate | date:'dd MMM'}}</p> 
      <a href="{{item.items[0].link}}">{{item.items[0].title}}</a>
    </div>
    <div class="col l6 s12">
      <ul>
        <li *ngFor="let single of item.items |slice: 1:10">
          <a href="{{single.link}}">{{single.title}}</a>