Define the interface
type Greeter interface {
Greet(username string)
}
Create an Object(struct and functions) that will implement the interface.
type NiceGreeter struct {}
func (g NiceGreeter) Greet(username string){
fmt.Printf("Hi %s ",username)
}
In the above, we can see that we simply implement the function of the interface.
We link the type (Object) to the function using (db DefaultDatabse) in the above code.
Use the interface
Define an Object(struct) that uses the interface
type Program struct {
Greeter Greeter
}
func (p Program) Execute(user string){
p.Greeter.Greet(user)
}
func main(){
//instantiate the greeter that implements Greeter
greeter := NiceGreeter{}
//instantiate the program with our greeter
p:= Program{
Greeter: greeter,
}
//execute
p.Execute("bob")
}
Full Code Example
package main
import "fmt"
type Greeter interface {
Greet(username string)
}
type NiceGreeter struct {}
func (g NiceGreeter) Greet(username string){
fmt.Printf("Hi %s ",username)
}
type Program struct {
Greeter Greeter
}
func (p Program) Execute(user string){
p.Greeter.Greet(user)
}
func main(){
greeter := NiceGreeter{}
p:= Program{
Greeter: greeter,
}
p.Execute("bob")
}
References
| Reference | URL |
|---|---|
| Interfaces - Go By Example | https://gobyexample.com/interfaces |
| Interfaces in Go | https://medium.com/rungo/interfaces-in-go-ab1601159b3a |