Go Design Pattern - decorative pattern

Dynamic object behavior change or add decorative patterns using object combinations of ways.

Anonymous combination of non-invasive interfaces and can be easily achieved by means of decorative patterns Go language.

Use anonymous combination, in decorator not need to explicitly define the transpose method of the original object.

Decorator Package 

Import ( 
	_ "FMT" 
) 

type interface BaseCal { 
	Cal () int 
} 

// Examples of computer 
type Computer struct { 
// what function nor 
} 

FUNC (the this * Computer) Cal () {int 
	return 0 
} 

FUNC NewComputer ( ) BaseCal { 
	return & Computer {} 
} 

type struct {addDecorator 
	BaseCal 
	NUM int 
} 

FUNC (the this addDecorator *) Cal () {int 
	return this.BaseCal.Cal () + this.num 
} 

// add a function to add Computer 
func NewAdd (CoMP BaseCal, NUM int) BaseCal { 
	return {& addDecorator 
		BaseCal: CoMP, 
		NUM: NUM, 
	} 
}

struct {MulDecorator type 
	BaseCal 
	NUM int 
} 

// Add to a * Computer function 
FUNC (the this MulDecorator *) Cal () {int 
	return this.BaseCal.Cal () * this.num 
} 

FUNC NewMul (CoMP BaseCal, NUM int) BaseCal { 
	return {& MulDecorator 
		BaseCal: CoMP, 
		NUM: NUM, 
	} 
}

　　

	c := decorator.NewComputer()
	c = decorator.NewAdd(c,10)
	c = decorator.NewMul(c,9)
	fmt.Println(c.Cal())//输出:90