Test Your JavaScript Skills : ES10 (JavaScript 2019) - 43

Introduction

Namaste, In this blog I will discuss 8 code scenarios on Javascript .

1. Identify the output of the below program

    let text = '   Namaste    ';
    let trimmedStart = text.trimStart();
    console.log(trimmedStart);
   

   a.Namaste

   b. Namaste

   c.error

   d.undefined

   e.null

   Answer:a

   Reason:The spaces from starting are removed.

2. Identify the output of the below program

    let text = '   Namaste    ';
    const trimmedEnd = text.trimEnd(); 
    console.log(trimmedEnd);
   

   a.Namaste

   b. Namaste

   c.Namas te

   d.undefined

   e.error

   Answer:b

   Reason:The spaces from end are removed.

3. Identify the output of the below program

    const entries = [['a', 1]];
    const obj = Object.fromEntries(entries);
    console.log(obj);
   

   a.['a','1']

   b.{a:1}

   c.{1:a}

   d.['1':'a']

   e.error

   Answer:b

   Reason:The array is converted to object.

4. Identify the output of the below program

    const entries = ['a', 1];
    const obj = Object.fromEntries(entries);
    console.log(obj);
   

   a.error

   b.{a:1}

   c.{1:a}

   d.{'a':'1'}

   e.undefined

   Answer:a

   Reason:The input is invalid hence error.

5. Identify the output of the below program

    const map = new Map([
        ["Lang", "JS"],    
      ]);
    let obj2 = Object.fromEntries(map);
    console.log(obj2);
   

   a.{'Lang':'JS'}

   b.{Lang:JS}

   c.{Lang:'JS'}

   d.{0:'JS'}

   e.error

   Answer:c

   Reason:The Map is converted to an object.

6. Identify the output of the below program

    const map = new Map(
        ["Lang", "JS"]    
      );
    let obj2 = Object.fromEntries(map);
    console.log(obj2);
   

   a.{'Lang':'JS'}

   b.{Lang:JS}

   c.{Lang:'JS'}

   d..{0:'JS'}

   e.error

   Answer:e

   Reason:The input is invalid.

7. Identify the output of the below program

    let mySymbol = Symbol('Database');
    console.log(mySymbol.description);
   

   a.Database

   b.Symbol

   c.Object

   d.Symbol(Object)

   e.error

   Answer:a

   Reason:The description property has value Database.

8. Identify the output of the below program

    const entries = [['data', false]];
    const obj = Object.fromEntries(entries);
    console.log(obj);
   

   a.['data', false]

   b.{'data', false}

   c.['data', false]

   d.{data: false}

   e.undefined

   Answer:d

   Reason:The array is converted to an object.