What are some examples of structs and interfaces in Go?

What are some examples of structs and interfaces in Go?

In Go, a struct is a composite data type that groups together variables. For example, you can define a struct like this:

type Person struct {
    Name string
    Age  int
}

An interface, on the other hand, defines a contract that types can implement. Here's an example:

type Greeter interface {
    Greet() string
}

You can then create a struct that implements this interface.

Can you show me how to implement an interface with a struct?

Sure! Here's how you can implement the Greeter interface with a Person struct:

func (p Person) Greet() string {
    return "Hello, my name is " + p.Name
}

Now, any Person can be used as a Greeter.

What happens if a struct doesn't implement all methods of an interface?

If a struct doesn't implement all the methods of an interface, it won't satisfy that interface. This means you can't use that struct where the interface type is expected.

Can you give me a real-world example of using structs and interfaces?

Absolutely! Consider a web application where you have different types of users. You can define a User struct and a Role interface. Each user type (like Admin, Guest) can implement the Role interface to define specific permissions.