Embedding pointer or not?

[GoingToGo]

As seen below Container struct has two non-pointer embedded fields - A and []B. It might contain a lot of data.

If I change my code and pass *Container to do() function, it will avoid re-copying so the app should be memory efficient. However, what I am trying to understand is that, should I also change embedded fields A and []B as *A and []*B as well to avoid copying or are they already copied when *Container passed?

Thanks

package main

type Container struct {
	ID int
	// ... more fields
	A A // or *A?
	B []B // or []*B?
}

type A struct {
	ID int
	// ... more fields
}

type B struct {
	ID int
	// ... more fields
}

func main() {
	c := Container{
		ID: 1,
		A:  A{
			ID: 491,
		},
		B:  []B{
			{
				ID: 87,
			},
		},
	}
	
	do(c)
}

func do(c Container) {
	// Do something with `c` but modification is not required.
}

[yi_zhang]

You don’t need to change field A and []B to pointer type to avoid memory copying. When you passing *Container to do() function, it’s the address of Container object that’s passed to the function.