Interfeyslar

Interfeys (interface) — bu metodlar ro’yxati. U turdan nima qilinishi kerakligini aytadi, qanday qilinishini emas. Go’da implementatsiya yashirin bo’ladi: implements degan kalit so’z yo’q — tur interfeysdagi metodlarni yozsa bo’lgani, u avtomatik shu interfeysni qondiradi.

interface.go


package main
 
import (
    "fmt"
    "math"
)
 
type Shape interface {
    Area() float64
}
 
type Rectangle struct{ W, H float64 }
type Circle struct{ R float64 }
 
func (r Rectangle) Area() float64 { return r.W * r.H }
func (c Circle) Area() float64    { return math.Pi * c.R * c.R }
 
func main() {
    // turli turlarni bitta slice ichida saqlaymiz
    shapes := []Shape{Rectangle{3, 4}, Circle{5}}
    for _, s := range shapes {
        fmt.Printf("Yuza: %.2f\n", s.Area())
    }
}


$ go run interface.go
Yuza: 12.00
Yuza: 78.54

Xulosa: Rectangle ham, Circle ham hech qayerda “men Shapeman” deb aytmadi — shunchaki Area()ni yozib qo’ydi, tamom, interfeys qondi.

Metodi yo’q interfeys — bu bo’sh interfeys, uni istalgan qiymat qondiradi. Uning qulay taxallusi (alias) — any. fmt esa maxsus Stringer interfeysini taniydi: tur String() string yozsa, chop etilganda o’sha o’zi chaqiriladi.

stringer-any.go


package main
 
import "fmt"
 
type Point struct{ X, Y int }
 
func (p Point) String() string {
    return fmt.Sprintf("(%d, %d)", p.X, p.Y)
}
 
func main() {
    var v any = Point{3, 7} // any = bo'sh interface
    fmt.Println(v)          // Stringer.String() chaqiriladi
    fmt.Printf("tur: %T\n", v)
}


$ go run stringer-any.go
(3, 7)
tur: main.Point

Xulosa: any istalgan qiymatni qabul qiladi, String() esa obyektni chiroyli ko’rinishda chiqarishning standart yo’li (bo’lmaganida {3 7} chiqardi).

Manba / batafsil: Go spec — Interface types , fmt.Stringer