Using reflect, how do you initialize value of a struct pointer field?

Question

package main

import (
    "fmt"
    "reflect"
)

type A struct {
    D *int
}

func main() {
    a := &A{}
    v := reflect.ValueOf(a)
    e := v.Elem()
    f := e.Field(0)
    z := reflect.Zero(f.Type().Elem())
    f.Set(z)
    fmt.Println(z)
}

panic: reflect.Set: value of type int is not assignable to type *int

how to set the *D to default value use reflect

`D` is a pointer, which starts out `nil`. It doesn't point anywhere, so it doesn't make sense to "set the *D" — newacct, May 10 '13 at 10:27

score 13 · Answer 1 · answered May 09 '13 at 07:52

13

You need to have a pointer value (*int), but the reflect documentation states for func Zero(typ Type) Value that:

The returned value is neither addressable nor settable.

In your case you can instead use New:

z := reflect.New(f.Type().Elem())

answered May 09 '13 at 07:52

ANisus

74,460
29
162
158

score 2 · Answer 2 · answered Apr 23 '14 at 21:17

2

try this

var i int
f.Set(reflect.ValueOf(&i))

answered Apr 23 '14 at 21:17

Arne

7,921
9
48
66

Using reflect, how do you initialize value of a struct pointer field?

2 Answers2

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