nil check is frequently seen in GoLang code especially for error check since GoLang's special error handling convention. In most cases, nil check is straight forward, but in interface case, it's a bit different and special care needs to be taken.Take a look at below code snippet and guess what the output will be.package mainimport ( "bytes" "fmt" "io")func check(w io.Writer) { if w != nil { fmt.Println("w is not nil") } fmt.Printf("w is %+v\n", w)}func main() { var b *bytes.Buffer check(b) fmt.Printf("b is %+v", b)}The output will be:w is not nilw is b is In the check() method, you would expe...