Embedded fields in structs

main.go

package main

import (
	"fmt"
)

type Fruit struct {
	Name string
	Color	string
}

// You can define functions on either the "base" ...
func (f* Fruit) Announce() {
	fmt.Printf("I am %s, and I am %s\n", f.Color, f.Name)
}

// Here adding "Fruit" is called embedding fields, and I've also seen "promoted fields" because they come from Fruit
type Avocado struct {
	Fruit
	IsRipe bool
}

// And we can define functions on the struct with embedded fields
// We cannot reference fields / methods for one of these classes on a parent. 
// E.g., Fruit could not have a function that uses IsRipe (although it would be appropriate huh?)
func (a * Avocado) IsReady() {
	if a.IsRipe {
		fmt.Printf("I am %s, and I am %s, and I am ripe!\n", a.Color, a.Name)
	} else {
		fmt.Printf("I am %s, and I am %s, and I am NOT ripe!\n", a.Color, a.Name)
	}

}

func main() {
	// This does not work!
	// avocado := Avocado{Name: "Harry the avocado", Color: "green", IsRipe: true}	
	// ./main.go:19:21: cannot use promoted field Fruit.Name in struct literal of type Avocado
	// ./main.go:19:48: cannot use promoted field Fruit.Color in struct literal of type Avocado

	// Instead, pass the "base" type to the underlying type
	avocado := Avocado{Fruit: Fruit{Name: "Harry the avocado", Color: "green"}, IsRipe: true}

	// This function is on the base struct
	avocado.Announce()
	// I am green, and I am Harry the avocado

	// This function
	avocado.IsReady()
	// I am green, and I am Harry the avocado, and I am ripe!

	// There is a proposal to make this easier!
	// https://github.com/golang/go/issues/9859
}

main.py

#!/usr/bin/env python3

class Fruit:
    def __init__(self, name, color):
        self.name = name
        self.color = color

    def Announce(self):
        print(f"I am {self.color}, and I am {self.name}")


class Avocado(Fruit):

    def __init__(self, name, color, is_ripe):
        super().__init__(name, color)
        self.is_ripe = is_ripe

    def IsReady(self):
        if self.is_ripe:
            print(f"I am {self.color}, and I am {self.name}, and I am ripe!")
        else:
            print(f"I am {self.color}, and I am {self.name}, and I am NOT ripe!")    

def main():

    avocado = Avocado(name = "Harry the avocado", color = "green", is_ripe=True)
    avocado.Announce()
    # I am green, and I am Harry the avocado

    avocado.IsReady()
    # I am green, and I am Harry the avocado, and I am ripe! 
   
if __name__ == "__main__":
    main()