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What is the default value of a map in Go language?

Here, we will learn about the map variable, and the default value of a map in Golang.
Submitted by IncludeHelp, on October 03, 2021

A map is a collection of unordered pairs of key-value. The default value of a map variable in the Go programming language is nil. The length of a nil map is o. But if you print the nil map – the output will be "map[]".

Example 1:

// Golang program to demonstrate the
// default value of a map

package main

import "fmt"

func main() {
	var x map[string]interface{}

	fmt.Println("Default value of a map is", x)
	fmt.Println("Length of an empty map is", len(x))
}

Output:

Default value of a map is map[]
Length of an empty map is 0

Example 2:

// Golang program to demonstrate the
// default values of maps

package main

import "fmt"

func main() {
	var x map[int]interface{}
	var y map[float64]interface{}
	var z map[string]interface{}

	// Printing the types & default values
	fmt.Printf("x: %T, %v\n", x, x)
	fmt.Printf("y: %T, %v\n", y, y)
	fmt.Printf("z: %T, %v\n", z, z)
}

Output:

x: map[int]interface {}, map[]
y: map[float64]interface {}, map[]
z: map[string]interface {}, map[]

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