Function declaration in Go - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a function declaration in Go?

A function declaration in Go defines a reusable block of code with a name, optional parameters, and an optional return type. It tells the program what the function does when called.

beginner

How do you declare a simple function named greet that prints "Hello" in Go?

You write:<br>

func greet() {
    fmt.Println("Hello")
}

<br>This declares a function named greet with no parameters and no return value.

intermediate

What is the syntax to declare a function with parameters in Go?

You list parameters inside parentheses after the function name, each with a name and type. For example:<br>

func add(a int, b int) int {
    return a + b
}

<br>This function takes two integers and returns an integer.

intermediate

Can a Go function return multiple values? How?

Yes, Go functions can return multiple values by listing return types in parentheses. Example:<br>

func swap(x, y string) (string, string) {
    return y, x
}

<br>This function returns two strings.

beginner

What keyword starts a function declaration in Go?

The keyword func starts every function declaration in Go. It signals that a function is being defined.

Which keyword is used to declare a function in Go?

A func

B function

C def

D fun

In Go, the keyword func is used to declare functions.

How do you declare a function named sum that takes two integers and returns an integer?

A function sum(a, b int) int {}

B func sum(a int, b int) {}

C func sum(a int, b int) int {}

D def sum(a int, b int) int {}

Option C correctly uses Go syntax with func, parameter types, and return type.

Can a Go function return more than one value?

A No, Go does not support return values

B No, only one return value is allowed

C Yes, but only if parameters are also multiple

D Yes, by listing multiple return types in parentheses

Go supports multiple return values by listing them in parentheses after the function parameters.

What is the correct way to declare a function with no parameters and no return value?

A func hello() {}

B func hello {}

C func hello() -> void {}

D function hello() {}

In Go, empty parentheses indicate no parameters, and no return type means no return value.

Which of these is a valid function declaration in Go?

A function greet(name string) string { return "Hi " + name }

B func greet(name string) string { return "Hi " + name }

C func greet(name string) { return "Hi " + name }

D func greet(name) string { return "Hi " + name }

Option B correctly declares parameter type and return type with proper syntax.

Explain how to declare a function in Go that takes parameters and returns a value.

Think about the order: func, name, parameters, return type, then body.

Describe how Go functions can return multiple values and why this might be useful.

Remember Go often returns error as a second value.