// Structs in go do not have inheritance likes classes
// however you can embed one struct inside another so that
// during use, the parts of the embedded struct behave exactly
// as parts of the enclosing struct. That said, at creation
// do do have to to extra work.
// Created  July 2021   gtowell
// Modified Sep 2022 gtowell

package main

import "fmt"

// a simple struct
type s1 struct {
	a int
	b int
}

// the struct s1 is in s2, but must be referred to through c
type s2 struct {
	c s1
	d int
}

// s1 is embedded in s3. It does not have an independent name
// This may cause some confusion if s1 sand s3 have elements of the
// same name but a different type
type s3 struct {
	s1
	a float32
	d int
}
func s3make(a, b, c int) s3 {
	return s3{s1:s1{a:a, b:b}, d:c, a:float32(a*2)}
}

func main() {
	as1 := s1{a:2, b:3}
	fmt.Println(as1)

	var as2 s2
	as2 = s2{c:s1{a:2, b:3}, d:5}
	fmt.Println(as2)
	fmt.Println(as2.c.a)

	as3 := s3make(4, 5, 7)
	fmt.Printf("%+v\n", as3);
	fmt.Printf("as3.a: %f\n", as3.a);
	// get to the embedded a through name of its struct
	fmt.Printf("as3.s1.a: %d\n", as3.s1.a);
}