traits.go

package main

import "log"

type EyeReq interface {
	setI(int)
	getI() int
}

type EyeTrait struct {
	EyeReq
}

func (f EyeTrait) eye() {
	f.setI(10)
}

/////////////////////////

type JayReq interface {
	setJ(int)
	getJ() int
}

type JayTrait struct {
	JayReq
}

func (f JayTrait) jay() {
	f.setJ(20)
}

///////////////////////////

type Cl struct {
	i, j int
}

func (cl *Cl) getI() int {
	return cl.i
}
func (cl *Cl) setI(i int) {
	cl.i = i
}

func (cl *Cl) getJ() int {
	return cl.j
}
func (cl *Cl) setJ(j int) {
	cl.j = j
}

func (cl *Cl) WithEyeTrait() EyeTrait {
	return EyeTrait{cl}
}
func (cl *Cl) WithJayTrait() JayTrait {
	return JayTrait{cl}
}

///////////////////////////////////////

type EyeJayTrait struct {
	EyeTrait
	JayTrait
}

func (cl *Cl) WithEyeJayTrait() EyeJayTrait {
	return EyeJayTrait{
		EyeTrait: cl.WithEyeTrait(),
		JayTrait: cl.WithJayTrait(),
	}
}

////////////////////////////
///////////////////////////////////////////
func main() {
	cl := Cl{}
	//	clFoo := cl.WithEyeTrait()
	//	clFoo.eye()
	//	clBar := cl.WithJayTrait()
	//	clBar.jay()

	clFooBar := cl.WithEyeJayTrait()
	clFooBar.eye()
	clFooBar.jay()

	log.Printf("cl.getI() = %+v\n", cl.getI())
	log.Printf("cl.getJ() = %+v\n", cl.getJ())
}