JavaScript · all questions

Array And Function
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38

Questions

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Q21

Do functions in JavaScript necessarily return a value ?

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Q22

Consider the following code snippet :

var tensquared = (function(x) {return x*x;}(10));

Will the above code work ?

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Q23

Consider the following code snippet :

var string2Num=parseInt("123xyz");

The result for the above code snippet would be :

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Q24

If you have a function f and an object o, you can define a method named m of o with

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Q25

For the below mentioned code snippet:

var o = new Object();

The equivalent statement is:

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Q26

What is the difference between the two lines given below ?

!!(obj1 && obj2);
(obj1 && obj2);

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Q27

Consider the following code snippet :

var c = counter(), d = counter(); 
c.count()
d.count() 
c.reset() 
c.count() 
d.count()

The state stored in d is :

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Q28

Consider the following code snippet :

var c = counter(), d = counter(); 
function constfuncs() 
{
    var funcs = [];
    for(var i = 0; i < 10; i++)
        funcs[i] = function() { return i; };
    return funcs;
}
var funcs = constfuncs();
funcs[5]()

What does the last statement return ?

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Q29

What kind of scoping does JavaScript use?

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Q30

What must be done in order to implement Lexical Scoping?

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Q31

What is a closure?

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Q32

Which of the following are examples of closures?

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Q33

Which of the following uses a lot of CPU cycles?

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Q34

Consider the following code snippet :

var scope = "global scope";
function checkscope() {
var scope = "local scope"; 
function f() 
{ 
     return scope; 
}
return f;

What is the function of the above code snippet?

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Q35

What is the fundamental rule of lexical scoping?

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Q36

What is the opposite approach to the lexical scoping?

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Q37

What is the purpose of the dynamic scoping?

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Q38

Which of the algorithmic languages is lexical scoping standardized in?

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