use unsafe to convert two different types and modify them

unsafe_converter.go

package main

import (
	"fmt"
	"unsafe"
)

type A struct {
	ID      int
	Name    string
	Country string
}

type B struct {
	ID   int
	Name string
}

func main() {
	aSlice := []*A{
		&A{
			ID:      1,
			Name:    "name-1",
			Country: "country-1",
		},
		&A{
			ID:      2,
			Name:    "name-2",
			Country: "country-2",
		},
	}
	aSlice = nil

	changeID(aSlice)

	for _, v := range aSlice {
		fmt.Println(v)
	}
}

func changeID(x []*A) {
	bslice := *(*[]*B)(unsafe.Pointer(&x))
	for i := range bslice {
		bslice[i].ID += 10
	}
}