interfaces.slide

Interfaces
23 Feb 2018

Adrian Lanzafame
adrianlanzafame92@gmail.com
@LanzafameAdrian

* Interfaces

Interfaces in Go provide a way to specify the behavior of an object: if something can do this, then it can be used here.

Distinction between an interface type and an interface value:

    // Pusher is an interface type.
    type Pusher interface {
        Push()
    }

    // p is an empty interface value.
    var p interface{}

.link https://play.golang.org/p/xf0F5MOM5r2

* Behaviour not State

Example of OOP-like type hierarchies:

.link https://play.golang.org/p/r6to0aMm6I

Example of grouping by  behaviour:

.link https://play.golang.org/p/yOj1zJCRlj

* Composition

Example of interface composition:

.link https://play.golang.org/p/s7B4mmIvtj

* Internals of an Interface

What is an interface value?

.image interfaces/interface-internal.png

* Rule of Thumb

_Accept_interfaces,_return_structs._
.caption Jack Lindamood