On Fri, Apr 3, 2020 at 7:10 PM joe mcguckin <j...@via.net> wrote: > I see some code like: > > r.NotFoundHandler =http.HandlerFunc(notfound) > > Where notfound() has the signature of > > func notfound(w http.ResponseWriter, r *http.Request) > > What is HandlerFunc() doing? It’s not a function. Is it some sort of type > coercion or casting? > I can see how casting that might work with simple values > (e.g.numbers,integers, etc) but functions? >
It is a function that returns a function: https://golang.org/pkg/net/http/#HandlerFunc.ServeHTTP. See also, https://golang.org/src/net/http/server.go?s=61783:61843#L2001. I'm guessing you've never used a language where functions are first-class objects that can be used indirectly; as opposed to direct calls you can search for using your editor/IDE. As the documentation states, it is an adapter that converts one function type into another. -- Kurtis Rader Caretaker of the exceptional canines Junior and Hank -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/CABx2%3DD_cjFYnhoap0FtsbP5hLsc7RjcWGf1o5EFsb7Hzhu68%2BA%40mail.gmail.com.
