reflect.IsValid() 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.IsValid() Function in Golang is used to check whether v represents a value. To access this function, one needs to imports the reflect package in the program.

Syntax:

func (v Value) IsValid() bool

Parameters: This function does not accept any parameter.

Return Value: This function returns whether v represents a value or not.

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

Example 1:

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

package main

import (
    "fmt"
    "reflect"
)

// Main function
func main() {

    // Use of IsValid() method
    fmt.Println(reflect.Value{}.IsValid())
    fmt.Println(reflect.ValueOf(nil).IsValid())
}

Output:

false
false

Example 2:

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

package main

import (
    "fmt"
    "reflect"
)

// Main function
func main() {
    var i *int
    v := reflect.ValueOf(i)
    v2 := v.Elem()

    // Use of IsValid() method
    fmt.Println(v2.IsValid())
    fmt.Println(reflect.ValueOf(nil).IsValid())

    fmt.Println(reflect.Indirect(v).IsValid())

}

Output:

false
false
false