What will be the output of the following code? var counter = (function() { var count = 0; return function() { return ++count; }; })(); console.log(counter()); console.log(counter());
A). 1, 2
B). 0, 1
C). undefined, undefined
D). 2, 4
Which of the following is true about functions in JavaScript?
A). Functions can be assigned to variables
B). Functions can be passed as arguments to other functions
C). Functions can be returned from other functions
D). All of the above
What will be the output of the following code? var double = function(x) { return x * 2; }; console.log(double(5));
A). 10
B). 5
C). undefined
D). double
Which of the following is an example of using a function as a return value?
A). function outer() { return function() { alert('Inner'); }; }
B). function outer() { function() { alert('Inner'); }; return; }
C). function outer() { function() { alert('Inner'); }; }
D). function outer() { return function { alert('Inner'); }; }
How do you define a function using a function expression?
A). var myFunc = function() { alert('Hello'); };
B). function myFunc() { alert('Hello'); }
C). var myFunc = function { alert('Hello'); };
D). var myFunc() { alert('Hello'); }
How can you store a function as a property of an object?
A). var obj = { method: function() { alert('Hello'); } };
B). var obj = { method: alert('Hello'); };
C). var obj = { method: function { alert('Hello'); } };
D). var obj = { function() { alert('Hello'); } };
What will be the output of the following code? var sayHi = function() { return 'Hi'; }; console.log(sayHi());
A). Hi
B). undefined
C). sayHi
D). function
How can you invoke a function stored in a variable doSomething?
A). doSomething();
B). call doSomething;
C). doSomething[];
D). invoke(doSomething);
What is the output of the following code? var person = { name: 'Alice', greet: function() { return 'Hello, ' + this.name; } }; console.log(person.greet());
A). Hello, Alice
B). Hello, undefined
C). Hello, name
D). undefined
Which of the following correctly demonstrates a function returning another function?
A). function outer() { return function() { alert('Inner'); }; }
B). function outer() { function() { alert('Inner'); } return; }
C). function outer() { function() { alert('Inner'); }; }
D). function outer() { return function { alert('Inner'); }; }