..brief insight into the usage of common JS ES6 methods

gistfile1.js

var arr = String('aminu;ocholi;oketta;odinma;mohammed;fidelis;james;brown;').split(';');

var students = [
    { name: 'aminu', age: 9, class: 'primary 6' },
    { name: 'delilah', age: 84, class: 'primary 6' },
    { name: 'mary', age: 19, class: 'primary 6' },
    { name: 'sujim', age: 12, class: 'primary 6' },
    { name: 'Mohammed', age: 29, class: 'primary 6' },
    { name: 'Tango', age: 84, class: 'primary 6' },
    { name: 'Maimuna', age: 69, class: 'primary 6' },
    { name: 'tobi', age: 3, class: 'primary 6' }
];


var scores = [34, 567, 323, 11, 665, 78, 3, 6, 88, 2];
var sorted = scores.sort((a, b) => b - a);

var filtered = students.filter((a) => a.age < 20).sort((a, b) => a.age - b.age);  using the sort. 

//when sorting, keep in mind that ... 
sort((a, b) => a - b)  // for ascending...  from 0 to 100
sort((a, b) => b - a)  // for descending... from 100 to 0

console.log(filtered)

var totalAges = students.reduce((a, c) => a + c.age, 0);  //initial value of 0

console.log(totalAges)

//for Object destructuring.. and works same for array.... 
const {name, age} = students[2];
console.log(`Student 2 = ${name} and he is ${age}yrs old`); // Student 2 = mary and he is 19yrs old

//then for using the spread operator... 
let newStudent = {name:'Tolani', age:13, class:'primary 4'};
allStudents = {...students, newStudent}; //spread the object and lay its elements then include an extra element. 

// this code is the same as ... saying. 
students.push(newStudent); //gives yout he same output... 

/*
  where you can push a new code into a new array, you can just spread the elements out and cast them either as an object or an array... 
 as the case may be... 
*/

//forEach 
students.forEach(student => {
    //do whatever you want with each student... 
});