What will be the output of the following JavaScript code?
int a==2;
int b=4;
int ans=a+b;
print(ans);
int b=4;
int ans=a+b;
print(ans);
2
6
0
error
Correct Answer :
D. error
Explanation: The following code will generate into an error output as a comparator operator is used outside of if statement. A single equalto (=) operator is used for initialization.
Related Questions
What is the observation made in the following JavaScript code?
var count = [1,,3];
The omitted value takes undefined
This results in an error
This results in an exception
The omitted value takes an integer value
What will be the equivalent output of the following JavaScript code snippet?
x = ~-y;
w = x = y = z;
q = a?b:c?d:e?f:g;
w = x = y = z;
q = a?b:c?d:e?f:g;
x = ~(-y); w = (x = (y = z));
q = a?b:(c?d:(e?f:g));
x = a?b:(c?d:(e?f:g));
q = ~(-y); w = (x = (y = z));
x = (x = (y = z));w = ~(-y);
q = a?b:(c?d:(e?f:g));
x = ~(-y); w = (x = (y = z));
q = (c?d:(e?f:g));
What will be the output of the following JavaScript code?
const obj = {prop: 12};
Object.preventExtensions(obj);
console.log( Object.isExtensible(obj));
Object.preventExtensions(obj);
console.log( Object.isExtensible(obj));
12
false
true
error
What will be the shift() output of the following JavaScript code?
var a = [];
a.unshift(1);
a.unshift(22);
a.shift();
a.unshift(3,[4,5]);
a.shift();
a.shift();
a.shift();
a.unshift(1);
a.unshift(22);
a.shift();
a.unshift(3,[4,5]);
a.shift();
a.shift();
a.shift();
1
[4,5]
[3,4,5]
Exception is thrown
The function definitions in JavaScript begins with _____________
Identifier and Parentheses
Return type and Identifier
Return type, Function keyword, Identifier and Parentheses
Identifier and Return type
Consider the following code snippet.
for(var p in o)
console.log(o[p]);
The above code is equivalent to which code?
console.log(o[p]);
for (var i = 0;i < a.length;i++)
console.log(a[i]);
for (int i = 0;i < a.length;i++)
console.log(a[i]);
for (var i = 0;i <= a.length;i++)
console.log(a[i]);
for (var i = 1;i < a.length;i++)
console.log(a[i]);
What will be the output of the following JavaScript code?
const object1 = {
property1: 20
};
console.log(Object.is(object1));
property1: 20
};
console.log(Object.is(object1));
20
true
false
error
What will be the output of the following JavaScript code?
7.25
-7.25
7
-7
What is the prototype represents in the following JavaScript code snippet?
function f() {};
Function f
A custom constructor
Prototype of a function
Not valid
The generalised syntax for a real number representation is __________
[digits][.digits][(E|e)[(+|-)]digits]
[digits][+digits][(E|e)[(+|-)]digits]
[digits][(E|e)[(+|-)]digits]
[.digits][digits][(E|e)[(+|-)]digits]
What will happen if reverse() and join() methods are used simultaneously?
Reverses and stores in the same array
Reverses and concatenates the elements of the array
Reverses
Stores the elements of an array in normal order
The purpose of extensible attribute is to __________
make all of the own properties of that object non configurable
to configure and bring a writable property
lock down objects into a known state and prevent outside tampering
to include new properties into the object
In the following switch syntax, the expression is compared with the case labels using which of the following operator(s)?
switch(expression)
{
statements
}
{
statements
}
==
equals
equal
===
Which of the operator is used to test if a particular property exists or not?
in
exist
within
exists
What will be the output of the following JavaScript code?
const object1 = {};
a = Symbol('a');
b = Symbol.for('b');
object1[a] = 'harry';
object1[b] = 'derry';
const objectSymbols = Object.getOwnPropertySymbols(object1);
console.log(objectSymbols.length);
a = Symbol('a');
b = Symbol.for('b');
object1[a] = 'harry';
object1[b] = 'derry';
const objectSymbols = Object.getOwnPropertySymbols(object1);
console.log(objectSymbols.length);
0
2
1
Error
Consider the following code snippet :
var tensquared = (function(x) {return x*x;}(10));
Will the above code work ?
Yes, perfectly
Error
Exception will be thrown
Memory leak
The function stops its execution when it encounters?
continue statement
break statement
goto statement
return statement
If you have a function f and an object o, you can define a method named m of o with
o.m=m.f;
o.m=f;
o=f.m;
o=f;
What happens in the following javaScript code snippet?
var count = 0;
while (count < 10)
{
console.log(count);
count++;
}
while (count < 10)
{
console.log(count);
count++;
}
The values of count are logged or stored in a particular location or storage
The value of count from 0 to 9 is displayed in the console
An error is displayed
An exception is thrown
What is a block statement in JavaScript?
conditional block
block that contains a single statement
both conditional block and a single statement
block that combines multiple statements into a single compound statement
JavaScript Code can be called by using ____________
RMI
Triggering Event
Preprocessor
Function/Method
Which is a more efficient JavaScript code snippet?
Code 1 :
for(var num=10;num>=1;num--)
{
document.writeln(num);
}
Code 2 :
var num=10;
while(num>=1)
{
document.writeln(num);
num++;
}
{
document.writeln(num);
}
while(num>=1)
{
document.writeln(num);
num++;
}
Code 1
Code 2
Both Code 1 and Code 2
Cannot Compare
What will the following code snippet work? If not, what will be the error?
function tail(o)
{
for (; o.next; o = o.next) ;
return o;
}
{
for (; o.next; o = o.next) ;
return o;
}
No, this will throw an exception as only numerics can be used in a for loop
No, this will not iterate
Yes, this will work
No, this will result in a runtime error with the message Cannot use Linked List
JavaScript is a _______________ language.
Object-Oriented
High-level
Assembly-language
Object-Based
Which is an equivalent code to invoke a function m of class o that expects two arguments x and y?
o(x,y);
o.m(x) && o.m(y);
m(x,y);
o.m(x,y);
What will be the output of the following JavaScript code?
var grade='A';
var result;
switch(grade)
{
case 'A':
result+=10;
case 'B':
result+= 9;
case 'C':
result+= 8;
default:
result+= 0;
}
document.write(result);
var result;
switch(grade)
{
case 'A':
result+=10;
case 'B':
result+= 9;
case 'C':
result+= 8;
default:
result+= 0;
}
document.write(result);
10
27
8
0
What will be the output of the following JavaScript code?
function equalto()
{
int num=10;
if(num===10)
return true;
else
return false;
}
{
int num=10;
if(num===10)
return true;
else
return false;
}
true
false
runtime error
compilation error
When an empty statement is encountered, a JavaScript interpreter __________
Ignores the statement
Prompts to complete the statement
Throws an error
Shows a warning
A conditional expression is also called a _______________
Alternative to if-else
Immediate if
If-then-else statement
Switch statement
Do functions in JavaScript necessarily return a value?
It is mandatory
Not necessary
Few functions return values by default
some functions do not return any value