go interface hackery

interface_ptr.go

package main

import "fmt"

func main() {
	s1, asc1 := FindAsc(1)
	s2, asc2 := FindAsc(2)
	s3, asc3 := FindAsc(3)
	s4, asc4 := FindAsc(4)

	fmt.Println(fmt.Sprintf(s1, asc1, *((*asc1).(*Asc))))

	fmt.Println(fmt.Sprintf(s2, (*asc2).Adsr(2), *((*asc2).(*Asc))))

	fmt.Print(fmt.Sprintf(s3, asc3, *((*asc3).(*Asc))))
	fmt.Println(fmt.Sprintf(string(db.Find((*asc3).Adsr(3))), asc3, *(*asc3).(*Asc)))

	fmt.Print(fmt.Sprintf(s4, asc4, *((*asc4).(*Asc))))
	fmt.Println(fmt.Sprintf(string(db.Find((*asc4).Adsr(2))), asc4, *(*asc4).(*Asc)))

}

type DB map[int]StoredAsc

var db = &DB{1: StoredAsc("a"), 2: StoredAsc("b"), 3: StoredAsc("c"), 4: StoredAsc("d")}

func (d *DB) Find(as *AdSRer) StoredAsc {
	if v, ok := (*d)[int(*(*as).(*Asc))]; ok {
		return StoredAsc(fmt.Sprint("[", as, "] -> ", *((*as).(*Asc)), " :-: ", v, " [%v] -> %v\n"))
	}
	panic(fmt.Errorf("db.Find(%v) failed.", int(*(*as).(*Asc))))

}

type AdSRer interface {
	Adsr(id int) *AdSRer
}

type Asc int
type StoredAsc string

func (asc *Asc) Adsr(id int) *AdSRer {
	*asc = Asc(id)
	a := AdSRer(asc)
	return &a
}

func FindAsc(id int) (val string, asc *AdSRer) {
	asc = AdSRer(new(Asc)).Adsr(id)
	val = string(db.Find(asc))
	return
}

output:

[0x1040a120] -> 1 :-: a [0x1040a120] -> 1

[0x1040a158] -> 2 :-: b [0x1040a1f0] -> 2

[0x1040a188] -> 3 :-: c [0x1040a188] -> 3
[0x1040a208] -> 3 :-: c [0x1040a188] -> 3

[0x1040a1b8] -> 4 :-: d [0x1040a1b8] -> 4
[0x1040a248] -> 2 :-: b [0x1040a1b8] -> 2

Program exited.