functions.md

Functions

1. What will be the Output??

   function setName() {
      this.name = 'devkode';
   }
   setName();
   console.log(this.name);

   • A: ‘devkode’
   • B: undefined
   • C: An Error will be thrown
   • D: null
   
   
   Answer

   Option: A

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2. What will be the output ?

   function fun(num1) {
       var num2 = 6;
       function TDK() {
           var num3 = 10;
           console.log(num1 * num2 * num3)
       }
       return TDK;
   }
   
   var TeamDevKode = fun(5)
   TeamDevKode ()

   • A: undefined
   • B: 0
   • C: 300
   • D: infinity
   
   
   Answer

   Option: C

---

3. What is the output ?

   const animal = {
     animal_name: "cat",
     action: function () {
       console.log(`${this.animal_name} is doing action`);
     }
   };
   
   setTimeout(animal.action, 1000);

   • A: cat is doing action
   • B: undefined is doing action
   • C: null is doing action
   • D: error
   
   
   Answer

   Option: B

---

4. What is the output ?

   const animal = {
     animal_name: "cat",
     action: function () {
       console.log(`${this.animal_name} is doing action`);
     }
   };
   
   setTimeout(function () {
     animal.action();
   }, 1000);

   • A: cat is doing action
   • B: undefined is doing action
   • C: null is doing action
   • D: error
   
   
   Answer

   Option: A

---

5. What is the output ?

   const animal = {
     animal_name: "cat",
     action: function () {
       console.log(`${this.animal_name} is doing action`);
     }
   };
   
   let func = animal.action.bind(animal);
   setTimeout(func, 1000);

   • A: null is doing action
   • B: undefined is doing action
   • C: cat is doing action
   • D: error
   
   
   Answer

   Option: C

---

6. What is the output ?

   function getFunc() {
     let value = "Hey !";
   
     let func = new Function("console.log(value)");
   
     return func;
   }
   
   getFunc()();

   • A: Hey !
   • B: error: value is not defined
   • C: null
   
   
   Answer

   Option: B

---

7. What is the output ?

   function getFunc() {
     let value = "Hello Friends !";
     let func = () => {
       alert(value);
     };
     return func;
   }
   
   getFunc()();

   • A: Hey !
   • B: error: value is not defined
   • C: Hello Friends !
   • D: null
   
   
   Answer

   Option: C

---

8. What is the output ?

   x = 1;
   function func() {
     this.x = 2;
     return x;
   }
   let a = new func();
   console.log(a.x);

   • A: 1
   • B: 2
   • C: undefined
   
   
   Answer

   Option: B

---

9. What will be the output ?

   let arr = Array.from(Array(10).keys());
   function func(a) {
     console.log(arguments.length);
   }
   func(arr);
   func(...arr);

   • A: 10 10
   • B: 10 1
   • C: 1 10
   • D: 1 1
   
   
   Answer

   Option: C

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10. What will be the output ?

    function func(a, b) {
      arguments[1] = 2;
      console.log(b);
    }
    func(1);

    • A: 2
    • B: undefined
    • C: 1
    • D: null
    
    
    Answer

    Option: B

---

11. What will be the output ?

    var x = 3;
    var obj = {
      x: 2,
      foo: {
        x: 1,
        bar: function () {
          return this.x;
        },
      },
    };
    var func = obj.foo.bar;
    console.log(func());
    console.log(obj.foo.bar());

    • A: 3 1
    • B: undefined 1
    • C: 1 1
    • D: 2 1
    
    
    Answer

    Option: A

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12. What will be the output ?

    var foo = function foo() {
      console.log(foo === foo);
    };
    foo();

    • A: false
    • B: true
    • C: error
    
    
    Answer

    Option: B

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13. What will be the output ?

    function getAge() {
      'use strict';
      age = 21;
      console.log(age);
    }
    
    getAge();

    • A: 21
    • B: undefined
    • C: ReferenceError
    • D: TypeError
    
    
    Answer

    Option: C

---

14. What will be the output ?

    const obj = { 1: 'a', 2: 'b', 3: 'c' };
    const set = new Set([1, 2, 3, 4, 5]);
    
    obj.hasOwnProperty('1');
    obj.hasOwnProperty(1);
    set.has('1');
    set.has(1);

    • A: false true false true
    • B: false true true true
    • C: true true false true
    • D: true true true true
    
    
    Answer

    Option: C

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15. What will be the output ?

    var num = "10";
    (function () {
    	console.log(num);
      var num = "50";
      console.log(num);}
      )();

    • A: undefined 50
    • B: 50 50
    • C: 10 10
    
    
    Answer

    Option: A

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