MCQs on Functions | Go

Master the essentials of Functions in Go with this comprehensive quiz. Test your knowledge on defining and calling functions, handling parameters and return values, and understanding anonymous functions and closures in Go programming.

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MCQs on Functions in Go

Defining and Calling Functions

1. How do you define a function in Go?
   a) def functionName() {}
   b) function functionName() {}
   c) func functionName() {}
   d) func functionName() -> {}
2. Which keyword is used to define a function in Go?
   a) method
   b) func
   c) function
   d) def
3. What is the correct way to call a function in Go?
   a) call functionName()
   b) functionName()
   c) execute functionName()
   d) invoke functionName()
4. What will be the output of the following Go code?
   func main() { fmt.Println("Hello World") }
   a) Error: fmt is undefined
   b) Hello World
   c) World Hello
   d) Compilation error
5. In Go, which part of the function declaration comes after the function name?
   a) Parameters
   b) Return type
   c) Function body
   d) Method
6. Which is the correct function signature in Go?
   a) func add(a, b int) int {}
   b) func add(int, int) {}
   c) func add(int a, int b) int {}
   d) func add(a, b int) {}
7. How are parameters defined in a Go function?
   a) Inside parentheses following the function name
   b) Using var before each parameter
   c) By separating them with commas after the function name
   d) Inside square brackets
8. Which of the following is a valid function declaration in Go?
   a) func sum(a int, b int) -> int {}
   b) func sum(a, b int): int {}
   c) func sum(a int, b int) int {}
   d) func sum(a, b: int) int {}
9. What is the return type of the following Go function?
   func add(a int, b int) int { return a + b }
   a) int
   b) a, b
   c) void
   d) int, int
10. Which function signature is incorrect in Go?
    a) func multiply(a int, b int) int
    b) func multiply(int a, int b) int
    c) func multiply(a, b int) int
    d) func multiply(int a, b int) {}

Parameters, Return Values, and Multiple Returns

11. How do you return multiple values from a function in Go?
    a) By separating the return types with commas
    b) By using an array or slice to return values
    c) By returning a tuple
    d) By using multiple return statements
12. Which of the following Go functions returns two values?
    func divide(a, b int) (int, int) { return a / b, a % b }
    a) divide
    b) int
    c) a, b
    d) a / b, a % b
13. What does the following Go function return?
    func swap(a, b int) (int, int) { return b, a }
    a) It returns the sum of a and b
    b) It returns two integers, swapping the values
    c) It returns the difference of a and b
    d) It does not return anything
14. What is the default return value of a Go function with no return statement?
    a) nil
    b) 0
    c) false
    d) Default values of the return types
15. What will the following Go function return?
    func getData() (int, string) { return 10, "Go" }
    a) 10
    b) "Go"
    c) (10, "Go")
    d) Error
16. In Go, if a function returns multiple values, what must be specified when calling the function?
    a) All return values need to be stored in variables
    b) Only one return value can be stored
    c) No variables need to be declared
    d) Only the first return value must be stored
17. What is the result of calling the following Go function?
    func greet() (string, int) { return "Hello", 10 }
    a) "Hello"
    b) 10
    c) ("Hello", 10)
    d) Error
18. How do you ignore one of the multiple return values in Go?
    a) By using the _ (underscore) symbol
    b) By using nil
    c) By leaving the second variable blank
    d) By passing false
19. How can you return different types of values from a Go function?
    a) By declaring a struct
    b) By using pointers
    c) By defining return types explicitly in the function signature
    d) By returning an interface
20. Which of the following is the correct syntax for multiple return values?
    a) return a, b
    b) return (a, b)
    c) return a and b
    d) return a or b

Anonymous Functions and Closures

21. What is an anonymous function in Go?
    a) A function without a name that can be called inline
    b) A function defined outside of a class
    c) A function that does not return any value
    d) A function defined in a separate file
22. How do you define an anonymous function in Go?
    a) func() {}
    b) def() {}
    c) function() {}
    d) func() -> {}
23. What is the typical use of an anonymous function in Go?
    a) For defining a function with no parameters
    b) For passing a function as an argument to another function
    c) For defining a recursive function
    d) For returning multiple values
24. Which of the following is an example of a closure in Go?
    func counter() func() int { count := 0 return func() int { count++ return count } }
    a) A function that adds numbers
    b) A function that returns an incrementing counter
    c) A function that performs arithmetic operations
    d) A function that prints data
25. In Go, closures can access:
    a) Only global variables
    b) Variables declared outside the function
    c) Only function parameters
    d) Static variables
26. What does the following Go closure do?
    func add(x int) func(int) int { return func(y int) int { return x + y } }
    a) Adds two integers passed to it
    b) Returns a new integer function
    c) Returns the sum of x and y
    d) Adds x to itself
27. How can you call an anonymous function in Go immediately after defining it?
    a) func() {}()
    b) {}()
    c) function() {}()
    d) call func() {}
28. What is the result of the following Go code?
    func main() { add := func(x, y int) int { return x + y } fmt.Println(add(5, 6)) }
    a) 5
    b) 11
    c) 5 6
    d) Error
29. How can a closure be useful in Go?
    a) By defining a global variable that all functions can access
    b) By retaining state between function calls without global variables
    c) By simplifying the code logic
    d) By optimizing the runtime performance
30. What is the primary feature of a closure in Go?
    a) It cannot modify external variables
    b) It can access and modify variables outside its scope
    c) It always returns values
    d) It is only used for recursion

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Answers Table

Qno	Answer
1	c) func functionName() {}
2	b) func
3	b) functionName()
4	b) Hello World
5	a) Parameters
6	a) func add(a int, b int) int {}
7	a) Inside parentheses following the function name
8	c) func sum(a int, b int) int {}
9	a) int
10	b) func multiply(int a, int b) int
11	c) By returning a tuple
12	a) divide
13	b) It returns two integers, swapping the values
14	d) Default values of the return types
15	c) (10, "Go")
16	a) All return values need to be stored in variables
17	c) ("Hello", 10)
18	a) By using the _ (underscore) symbol
19	c) By defining return types explicitly in the function signature
20	a) return a, b
21	a) A function without a name that can be called inline
22	a) func() {}
23	b) For passing a function as an argument to another function
24	b) A function that returns an incrementing counter
25	b) Variables declared outside the function
26	b) Returns a new integer function
27	a) func() {}()
28	b) 11
29	b) By retaining state between function calls without global variables
30	b) It can access and modify variables outside its scope