CSS

golang interface

type Shape interface {
    area() float64
    perimeter() float64
}

interfaces in golang

The interface is a collection of methods as well as it is a custom type.

golang interface function

type MathInterface interface {
	Added() int
	Subtract() int
}

type Math struct {
	x, y int
}

func (m *Math) Add() int {
	return m.x + m.y
}

func (m *Math) Subtract() int {
	return m.x - m.y
}

func main() {
	data := Math{}
	data.x = 5
	data.y = 3

	added := data.Add()
	subtract := data.Subtract()

	fmt.Println(added)
	fmt.Println(subtract)
}

golang interface function

type MathInterface interface {
	Added() int
	Subtract() int
}

type Math struct {
	x, y int
}

func (m *Math) Add() int {
	return m.x + m.y
}

func (m *Math) Subtract() int {
	return m.x - m.y
}

type HandlerMath struct {
	handler *Math
}

func NewMatch(math *Math) *HandlerMath {
	return &HandlerMath{handler: math}
}

func main() {
	data := NewMatch(&Math{})
	data.handler.x = 5
	data.handler.y = 3

	added := data.handler.Add()
	subtract := data.handler.Subtract()

	fmt.Println(added)
	fmt.Println(subtract)
}

Interfaces in Golang

package main

import (
  "fmt"
)

type animal interface {
  description() string
}

type cat struct {
  Type  string
  Sound string
}

type snake struct {
  Type      string
  Poisonous bool
}

func (s snake) description() string {
  return fmt.Sprintf("Poisonous: %v", s.Poisonous)
}

func (c cat) description() string {
  return fmt.Sprintf("Sound: %v", c.Sound)
}

func main() {
  var a animal
  a = snake{Poisonous: true}
  fmt.Println(a.description())
  a = cat{Sound: "Meow!!!"}
  fmt.Println(a.description())
}

//=> Poisonous: true
//=> Sound: Meow!!!

golang interface function

type MathInterface interface {
	Added() int
	Subtract() int
}

type Math struct {
	x, y int
}

func (m *Math) Add() int {
	return m.x + m.y
}

func (m *Math) Subtract() int {
	return m.x - m.y
}

func main() {
	data := Math{}
	data.x = 5
	data.y = 3

	added := data.Add()
	subtract := data.Subtract()

	fmt.Println(added)
	fmt.Println(subtract)
}

interface to int golang

iAreaId := val.(int)
iAreaId, ok := val.(int) // Alt. non panicking version 

interface in go

type SDLDriver struct {
    window *sdl.Window
    renderer *sdl.Renderer
}

type NativeDriver struct {
    someDataField *Whatever
}

type AnotherDriver struct {
    someDataField *Whatever
}