Polymorphism with Interfaces

work

package main

import (
    "fmt"
)

type Test interface{
    Run()
//  Debug()
}

type My struct{
    body string
}

func (m My)Run(){
    fmt.Println(m.body)
}

func main() {
    my :=  &My{body: "DOOOOOOOO"}
    fmt.Println("Hello, playground")
    testRun(my)
}

func testRun(t Test){
    t.Run()
}

↓

Hello, playground
DOOOOOOOO

Error

package main

import (
    "fmt"
)

type Test interface{
    Run()
//  Debug()
}

type My struct{
    body string
}

func (m My)Run(){
    fmt.Println(m.body)
}

func main() {
    my :=  &My{body: "DOOOOOOOO"}
    fmt.Println("Hello, playground")
    testRun(my)
}

func testRun(t Test){
    t.Run()
}

↓

./prog.go:23:9: cannot use my (type *My) as type Test in argument to testRun:
    *My does not implement Test (missing Debug method)