Printing Types

Part of the Fundamentals section of Coddy's GO journey — lesson 31 of 109.

In Go, we can display the type of a variable using the %T format verb with the fmt.Printf() function. Let's explore how to do this with different data types.

First, let's create variables of different types and print their types:

name := "Gopher"
age := 25
height := 1.85
isActive := true
    
fmt.Printf("name is type: %T\n", name)
fmt.Printf("age is type: %T\n", age)
fmt.Printf("height is type: %T\n", height)
fmt.Printf("isActive is type: %T\n", isActive)

After executing this code, we'll see the type of each variable shown on the screen:

name is type: string
age is type: int
height is type: float64
isActive is type: bool

The %T format verb tells Go to display the data type instead of the value itself. This is very helpful when you're not sure what type a variable is or when you're learning about Go's type system.

Challenge

Beginner

In this challenge, you'll practice using the %T format verb with fmt.Printf to display the types of different variables.

The code already has several variables of different types defined. Your task is to use fmt.Printf with the %T format verb to print out the type of each variable.

Cheat sheet

Use the %T format verb with fmt.Printf() to display the type of a variable:

name := "Gopher"
age := 25
height := 1.85
isActive := true

fmt.Printf("name is type: %T\n", name)
fmt.Printf("age is type: %T\n", age)
fmt.Printf("height is type: %T\n", height)
fmt.Printf("isActive is type: %T\n", isActive)

Output:

name is type: string
age is type: int
height is type: float64
isActive is type: bool

Try it yourself

package main

import "fmt"

func main() {
	// These variables are already defined for you
	age := 25
	price := 19.99
	isAvailable := true
	productName := "Wireless Headphones"
	
	// TODO: Use fmt.Printf with %T to print the type of the 'age' variable
	// The output should be: "The type of age is: int"
	
	// TODO: Use fmt.Printf with %T to print the type of the 'price' variable
	// The output should be: "The type of price is: float64"
	
	// TODO: Use fmt.Printf with %T to print the type of the 'isAvailable' variable
	// The output should be: "The type of isAvailable is: bool"
	
	// TODO: Use fmt.Printf with %T to print the type of the 'productName' variable
	// The output should be: "The type of productName is: string"
}