In Go, there is a powerful, and dreaded word… Interface.
Interfaces can provide flexability.
Animal, Dog & Cat
For an example, I’ve got the interface, and 2 structures…
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type Animal interface {
Name() string
Sound() string
}
type Dog struct {
name string
}
func (d *Dog) Name() string {
return d.name
}
func (d *Dog) Sound() string {
return "woof"
}
type Cat struct {
name string
}
func (c *Cat) Name() string {
return c.name
}
func (c *Cat) Sound() string {
return "meow"
}
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Now using this…
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import "fmt"
func main() {
var a1 Animal = &Dog{name: "Spot"}
var a2 Animal = &Cat{name: "Rex"}
fmt.Printf("%s says %s\n", a1.Name(), a1.Sound())
fmt.Printf("%s says %s\n", a2.Name(), a2.Sound())
}
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Please note how I made those 2 Animals.
In Go, an interface (in this case Animal), must have a Pointer (in this case, a pointer to a Dog, and a pointer to a Cat, in Go, they would be represented as *Dog and *Cat).
Once it is an Animal, you must use reflect to convert it from Animal to *Dog or *Cat