Multiple return values in Go - Mini Project: Build & Apply

Multiple return values in Go

📖 Scenario: Imagine you are writing a small program to calculate the area and perimeter of a rectangle. You want a function that can give you both results at the same time.

🎯 Goal: Create a Go program with a function that returns two values: the area and the perimeter of a rectangle. Then print these values.

📋 What You'll Learn

Create a function called rectangleMetrics that takes two int parameters: length and width.

The function rectangleMetrics must return two int values: the area and the perimeter.

Call the function with length = 5 and width = 3.

Print the returned area and perimeter values with clear labels.

💡 Why This Matters

🌍 Real World

Functions that return multiple values are common in Go for returning results and errors or multiple related results together.

💼 Career

Understanding multiple return values is important for writing clean, efficient Go code in real-world applications like web servers, tools, and data processing.

1

Create variables for rectangle dimensions

Create two int variables called length and width and set them to 5 and 3 respectively.

Go

package main

import "fmt"

func main() {
    // Create variables length and width
    // Your code here
}

Hint

Use := to declare and assign variables in Go.

2

Create the rectangleMetrics function

Create a function called rectangleMetrics that takes two int parameters named length and width. It should return two int values.

Go

package main

import "fmt"

func rectangleMetrics(length int, width int) (int, int) {
    // Your code here
}

func main() {
    length := 5
    width := 3
}

Hint

Calculate area as length * width and perimeter as 2 * (length + width). Return both values.

3

Call the function and store results

Call the function rectangleMetrics with length and width variables. Store the returned values in two variables called area and perimeter.

Go

package main

import "fmt"

func rectangleMetrics(length int, width int) (int, int) {
    area := length * width
    perimeter := 2 * (length + width)
    return area, perimeter
}

func main() {
    length := 5
    width := 3
    // Call rectangleMetrics and store results
    // Your code here
}

Hint

Use multiple assignment to receive both returned values.

4

Print the area and perimeter

Print the values of area and perimeter with the exact text: Area: followed by the area value, and Perimeter: followed by the perimeter value.

Go

package main

import "fmt"

func rectangleMetrics(length int, width int) (int, int) {
    area := length * width
    perimeter := 2 * (length + width)
    return area, perimeter
}

func main() {
    length := 5
    width := 3
    area, perimeter := rectangleMetrics(length, width)
    // Print area and perimeter
    // Your code here
}

Hint

Use fmt.Println to print each value with its label.