Js programming interview questions

1)
var fruits=["Water Melon","Plum","Apple","Grapes"];
let newData=[];
fruits.map(function(fruit){
    if(fruit.substr(2).length>3){
        // console.log(fruit);
        newData.push(fruit);
    }
    return newData;
})
console.log(newData);
Ans: [ 'Water Melon', 'Grapes' ]


2.    function is_domain(str){
        regexp=/^[a-z]+([.\:]{1}{a-z0-9]+)+\.[a-z]{2,6}$/
        if(str.match(regexp)){
            return true;
        }
        else return false;
        
    }
console.log(is_domain("www.jimbo.5.cn.in"));
console.log(is_domain("http://:google.com"));
console.log(is_domain("www.n5m.co.uKT"));
console.log(is_domain("www.lettySing.com"));

Ans : all false.

1.       A new feature of ES6 is the template literal (multiline string)
2.       ES6 provides the syntactic sugar to eliminate the redundancy of having to write x: x. You can simply write x once, and it will be converted tox: x (or something equivalent) under the hood. Here is the same function from above rewritten to use this new syntax: const getMousePosition = (x, y) => ({ x, y });
3.       Write Concise Declarative Functions with ES6
4.       When defining functions within objects in ES5, we have to use the keyword function as follows:
const person = {
  name: "Taylor",
  sayHello: function() {
    return `Hello! My name is ${this.name}.`;
  }
};
With ES6, you can remove the function keyword and colon altogether when defining functions in objects. Here's an example of this syntax:
 
const person = {
  name: "Taylor",
  sayHello() {
    return `Hello! My name is ${this.name}.`;
  }
};
Refactor the function setGear inside the object bicycle to use the shorthand syntax described above.
5.       Use getters and setters to Control Access to an Object
6.       Create a Module Script
<script type="module" src="filename.js"></script>
7.       Use export to Share a Code Block
const add = (x, y) => {
  return x + y;
}
 
export { add };
8.       Create a JavaScript Promise const myPromise = new Promise((resolve, reject) => {   });

Q) Array of array to single array?
let a =[["b","a"],["a","c"]];

let b=[]
for(let i=0;i<a.length;i++){
  b.push(...a[i])
}
// b.sort((a,b)=>a<b?1:-1)
for(let i=0;i<b.length;i++){
  for(let j=i;j<b.length;j++){
    if(b[i]<b[j]){
     let temp= b[i]
      b[i]= b[j]
      b[j]= temp
    }
  }
}

console.log(b)