Go言語における埋め込みによるインタフェースの部分実装パターン ref: https://qiita.com/tenntenn/items/e04441a40aeb9c31dbaf

file0.go

package main

import "fmt"

type Person struct {
    FirstName string
    LastName  string
}

func (p *Person) Name() string {
    return p.FirstName + " " + p.LastName
}

func main() {
    person := &Person{"Taro", "Yamada"}
    fmt.Println(person.Name())
}

file0.txt

package main

import "fmt"

type Person struct {
    FirstName string
    LastName  string
}

func (p *Person) Name() string {
    return p.FirstName + " " + p.LastName
}

func main() {
    person := &Person{"Taro", "Yamada"}
    fmt.Println(person.Name())
}

file1.go

package main

import "fmt"

type Person struct {
    FirstName string
    LastName  string
}

func (p *Person) Name() string {
    return p.FirstName + " " + p.LastName
}

type Named interface {
    Name() string
}

func printName(named Named) {
    fmt.Println(named.Name())
}

func main() {
    person := &Person{"Tarou", "Yamada"}
    printName(person)
}

file1.txt

package main

import "fmt"

type Person struct {
    FirstName string
    LastName  string
}

func (p *Person) Name() string {
    return p.FirstName + " " + p.LastName
}

type Named interface {
    Name() string
}

func printName(named Named) {
    fmt.Println(named.Name())
}

func main() {
    person := &Person{"Tarou", "Yamada"}
    printName(person)
}

file2.go

package main

import "fmt"

type Hoge struct {
    N int
}

type Piyo struct {
    Hoge
    M int
}

func main() {
    piyo := &Piyo{Hoge{1}, 2}
    fmt.Println(piyo.N, piyo.M)
    fmt.Println(piyo.Hoge.N, piyo.M)
}

file2.txt

package main

import "fmt"

type Hoge struct {
    N int
}

type Piyo struct {
    Hoge
    M int
}

func main() {
    piyo := &Piyo{Hoge{1}, 2}
    fmt.Println(piyo.N, piyo.M)
    fmt.Println(piyo.Hoge.N, piyo.M)
}

file3.go

package main

import "fmt"

type Gender int

const (
    Female = iota
    Male
)

type Person interface {
    Name() string
    Title() string
}

func New(gender Gender, firstName, lastName string) Person {
    p := &person{firstName, lastName}
    if gender == Male {
        return &male{p}
    } else {
        return &female{p}
    }
}

type person struct {
    firstName string
    lastName  string
}

func (p *person) Name() string {
    return p.firstName + " " + p.lastName
}

type female struct {
    *person
}

func (f *female) Title() string {
    return "Ms."
}

type male struct {
    *person
}

func (m *male) Title() string {
    return "Mr."
}

func printFullName(p Person) {
    fmt.Println(p.Title(), p.Name())
}

func main() {
    taro := New(Male, "Taro", "Yamada")
    printFullName(taro)

    hanako := New(Female, "Hanako", "Yamada")
    printFullName(hanako)
}

file3.txt

package main

import "fmt"

type Gender int

const (
    Female = iota
    Male
)

type Person interface {
    Name() string
    Title() string
}

func New(gender Gender, firstName, lastName string) Person {
    p := &person{firstName, lastName}
    if gender == Male {
        return &male{p}
    } else {
        return &female{p}
    }
}

type person struct {
    firstName string
    lastName  string
}

func (p *person) Name() string {
    return p.firstName + " " + p.lastName
}

type female struct {
    *person
}

func (f *female) Title() string {
    return "Ms."
}

type male struct {
    *person
}

func (m *male) Title() string {
    return "Mr."
}

func printFullName(p Person) {
    fmt.Println(p.Title(), p.Name())
}

func main() {
    taro := New(Male, "Taro", "Yamada")
    printFullName(taro)

    hanako := New(Female, "Hanako", "Yamada")
    printFullName(hanako)
}