reflect.Zero() Function in Golang with Examples

Go language provides inbuilt support implementation of run-time reflection and allowing a program to manipulate objects with arbitrary types with the help of reflect package. The reflect.Zero() Function in Golang is used to get the Value representing the zero value for the specified type. To access this function, one needs to imports the reflect package in the program.

Syntax:

func Zero(typ Type) Value

Parameters: This function takes the following parameters:

• typ : This parameter is the Type.

Return Value: This function returns the Value representing the zero value for the specified type.

Below examples illustrate the use of the above method in Golang:

Example 1:

// Golang program to illustrate
// reflect.Zero() Function

package main

import (
    "fmt"
    "reflect"
)

func main() {
    s := struct{ A int }{0}
    field := reflect.ValueOf(s).Field(0)

    fmt.Println(field.Interface())

    // use of Zero() method
    fmt.Println(reflect.Zero(field.Type()))

    fmt.Println(reflect.DeepEqual(field.Interface(), reflect.Zero(field.Type())))
}

Output:

0
0
false

Example 2:

// Golang program to illustrate
// reflect.Zero() Function

package main

import (
    "fmt"
    "reflect"
)

func main() {
    s := struct{ A int }{0}
    field := reflect.ValueOf(s).Field(0)

    fmt.Println(field.Interface())

    // use of Zero() method
    fmt.Println(reflect.Zero(field.Type()))
    fmt.Println(reflect.TypeOf(field.Interface()))

    // use of Zero() method
    fmt.Println(reflect.TypeOf(reflect.Zero(field.Type())))

    // use of Zero() method
    fmt.Println(reflect.DeepEqual(field.Interface(),
                       reflect.Zero(field.Type())))

    fmt.Println(reflect.DeepEqual(field.Interface(),
            int(reflect.Zero(field.Type()).Int())))
    fmt.Println(reflect.DeepEqual(s, struct{ A int }{} ))
    fmt.Println(reflect.DeepEqual(s, struct{ A int }{0} ))
}

Output:

0
0
int
reflect.Value
false
true
true
true