package main

import (
	"errors"
	"fmt"
	"os"
)

func main() {
	base := []int{1, 2, 3}
	alias := base[:2]
	clone := append([]int(nil), base...)
	alias[0] = 9
	if base[0] != 9 || clone[0] != 1 {
		panic("unexpected slice ownership")
	}
	fmt.Println(base[0], clone[0])
	err := fmt.Errorf("load config: %w", os.ErrNotExist)
	if !errors.Is(err, os.ErrNotExist) {
		panic("lost error cause")
	}
	fmt.Println(errors.Is(err, os.ErrNotExist))
}