Hands-On System Programming with Go

Custom-defined types

A package can define its own types by using the type defined definition expression, where definition is a type that shares a defined memory representation. Custom types can be defined by basic types:

type Message string    // custom stringtype Counter int       // custom integertype Number float32    // custom floattype Success bool      // custom boolean

They can also be defined by composite types like slices, maps, or pointers:

type StringDuo [2]string            // custom array   type News chan string               // custom channeltype Score map[string]int           // custom maptype IntPtr *int                    // custom pointertype Transform func(string) string  // custom functiontype Result struct {                // custom struct    A, B int}

They can also be used in combination with other custom ...