reflect.Elem() 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.Elem() Function in Golang is used to get the value that the interface v contains or that the pointer v points to. To access this function, one needs to imports the reflect package in the program.

Syntax:

func (v Value) Elem() Value

Parameters: This function does not accept any parameters.

Return Value: This function returns the value that the interface v contains.

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

Example 1:

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

package main

import (
    "fmt"
    "reflect"

)
type Book struct {
    Id    int
    Title string
    Price float32
    Authors []string
}

// Main function
func main() {
    book := Book{}

    //use of Elem() method
    e := reflect.ValueOf(&book).Elem()

    for i := 0; i < e.NumField(); i++ {
        varName := e.Type().Field(i).Name
        varType := e.Type().Field(i).Type
        varValue := e.Field(i).Interface()
        fmt.Printf("%v %v %v\n", varName, varType, varValue)
    }
}

Output:

Id int 0
Title string 
Price float32 0
Authors []string []

Example 2:

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

package main

import (
    "fmt"
    "reflect"
     "io"
     "os"
)

// Main function
func main() {

    //use of Elem() method
    writerType := reflect.TypeOf((*io.Writer)(nil)).Elem()

    fileType := reflect.TypeOf((*os.File)(nil))
    fmt.Println(fileType.Implements(writerType))
}

Output:

true