Interfaces in Go
An interface is a type that defines one or more method signatures.
Methods are not implemented, just their signature: the name, parameter types and return value type.
Something like this:
type Speaker interface {
Speak()
}
Now you could have a function accept any type that implements all the methods defined by the interface:
func SaySomething(s Speaker) {
s.Speak()
}
And we can pass it any struct that implements those methods:
type Speaker interface {
Speak()
}
type Person struct {
Name string
Age int
}
func (p Person) Speak() {
fmt.Println("Hello from " + p.Name)
}
func SaySomething(s Speaker) {
s.Speak()
}
func main() {
flavio := Person{Age: 39, Name: "Flavio"}
SaySomething(flavio)
}
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