Which of the following methods can help in avoiding global variables?
A). Using functions to encapsulate code
B). Using objects to namespace code
C). Using ES6 modules
D). All of the above
What happens if you declare a variable without var
, let
, or const
inside a function?
A). It becomes a global variable
B). It becomes a local variable
C). It throws an error
D). It becomes a constant
What is the output of typeof window
in a browser environment?
A). object
B). undefined
C). function
D). global
How can you access a global variable inside a function if it has the same name as a local variable?
A). By using the window
object
B). By using the global
object
C). By using a different name for the global variable
D). By using the this
keyword
What is the global object in a browser environment?
A). window
B). global
C). document
D). this
How do you declare a global variable inside a function?
A). Using var
B). Using let
C). Using const
D). Assigning to window
What is the output of console.log(globalVar);
if globalVar = 'Hello';
is assigned inside a function without using var
, let
, or const
?
A). Hello
B). undefined
C). error
D). null
What happens if you declare a variable inside a function with the same name as a global variable?
A). It creates a new local variable
B). It throws an error
C). It modifies the global variable
D). It assigns the global variable to null
What is the purpose of the global object in JavaScript?
A). To store local variables
B). To provide a namespace for global variables and functions
C). To define constants
D). To execute code in strict mode
What is the output of console.log(globalThis === window);
in a browser environment?
A). 1
B). 0
C). undefined
D). null