Q
In which scenario would redeclaring a variable with 'var' lead to an unintended consequence?

Answer & Solution

Answer: Option A
Solution:
Redeclaring a variable with 'var' in the same scope can lead to unintended consequences such as overwriting the previous variable, leading to potential bugs.
Related Questions on Average

What happens when you redeclare a variable with 'var' inside a function?

A). The variable is overwritten

B). The variable declaration is ignored

C). It throws an error

D). The function's scope is reset

Why is it recommended to use 'let' and 'const' over 'var' in modern JavaScript?

A). 'let' and 'const' are function-scoped

B). 'let' and 'const' prevent variable hoisting

C). 'let' and 'const' are block-scoped, reducing potential errors

D). 'let' and 'const' are faster

What happens if you try to redeclare a 'const' variable in JavaScript?

A). It will throw an error

B). The variable is overwritten

C). The variable is converted to 'let'

D). The program continues with a warning

Can you redeclare a 'let' variable in the same scope in JavaScript?

A). Yes

B). No

C). Only in strict mode

D). Only in non-strict mode

Which of the following statements about 'let' and 'const' is false?

A). Both 'let' and 'const' are block-scoped

B). Both 'let' and 'const' cannot be redeclared in the same scope

C). 'let' can be reassigned, 'const' cannot

D). Both 'let' and 'const' can be redeclared in different scopes

How does the scope of 'var' differ from 'let' and 'const' inside a function?

A). 'var' is block-scoped, 'let' and 'const' are function-scoped

B). 'var', 'let', and 'const' are all block-scoped

C). 'var' is function-scoped, 'let' and 'const' are block-scoped

D). 'var' and 'let' are block-scoped, 'const' is function-scoped

Which of the following correctly describes variable hoisting with 'var'?

A). 'var' declarations are not hoisted

B). Only the variable declaration is hoisted, not the initialization

C). Both declaration and initialization are hoisted

D). Only in strict mode 'var' declarations are hoisted

Which of the following statements is true regarding redeclaring variables in JavaScript?

A). You can redeclare 'var' variables within the same scope without errors

B). You can redeclare 'let' variables within the same scope without errors

C). You can redeclare 'const' variables within the same scope without errors

D). None of the above

Given 'var a = 1; var a = 2;', what is the value of 'a' after these statements execute?

A). 1

B). 2

C). Undefined

D). Syntax Error

What will happen if you try to use a variable before declaring it with 'let'?

A). It will return undefined

B). It will return null

C). It will throw a ReferenceError

D). It will return NaN