What are interfaces in Go and how do I use them?

Can you explain what interfaces are in Go?

Interfaces in Go are types that specify a contract of methods. Any type that implements those methods satisfies the interface.

How do I define an interface in Go?

You define an interface using the type keyword followed by the interface name and the method signatures it requires.

Can you give me an example of an interface in Go?

Sure! Here's a simple example:

type Animal interface {
    Speak() string
}

type Dog struct {}

func (d Dog) Speak() string {
    return "Woof!"
}

In this example, Animal is an interface with a Speak method.

How do I implement an interface in a struct?

To implement an interface, just define the methods of the interface in your struct. Go automatically recognizes it as implementing the interface.