Tour of Go 2.0

Slices are like references to arrays

A slice doesn’t own its data — it’s just a view into an underlying array. No copying happens when you slice.

Because of that, if you change an element through a slice, you’re changing the array. And if another slice points to the same part of that array, it sees the change too.

Try it: Notice how modifying b[0] also changes what a sees, because both slices overlap on the same underlying array.

main.go ▶ Run in Playground 
package main

import "fmt"

func main() {
	names := [4]string{
		"John",
		"Paul",
		"George",
		"Ringo",
	}
	fmt.Println(names)

	a := names[0:2]
	b := names[1:3]
	fmt.Println(a, b)

	b[0] = "XXX"
	fmt.Println(a, b)
	fmt.Println(names)
}