go generics test

example.go

package main

import (
	"errors"
	"fmt"
)

type Example interface {
	Init(config map[string]interface{})
}

type ExampleFactory[T Example] struct {
	config map[string]interface{}
}

func (self *ExampleFactory[T]) Get() T {
	var result = *new(T) // result := new(T) won't work
	result.Init(self.config)
	return result
}

type Db struct {
	vals map[string]bool
}

func (self *Db) Init(config map[string]interface{}) {
	if self == nil {
		panic(errors.New("db is nil"))
	}
	self.vals = map[string]bool{"initialized" : true}
}

func main() {
	factory := &ExampleFactory[*Db]{}
	db := factory.Get()
	fmt.Printf("Initialized? %v\n", db.vals["initialized"])
}