fix: fixed recusrive err

builder.go

@@ -30,23 +30,7 @@ func writeHeaders(writer http.ResponseWriter, builder Builder) {
 
 func DefaultResponderHandler(writer http.ResponseWriter, request *http.Request, builder Builder) {
 	if builder.err != nil {
-		if builder, ok := builder.err.(Builder); ok {
-			builder.Handle(writer, request)
-
-			return
-		}
-
-		if responder, ok := builder.err.(Responder); ok {
-			responder.
-				Respond(request).
-				Handle(writer, request)
-
-			return
-		}
-
-		NewProblem(builder.err, builder.status).
-			Respond(request).
-			Handle(writer, request)
+		handleError(writer, request, builder.err)
 
 		return
 	}

handler.go

@@ -21,11 +21,21 @@ func handleError(writer http.ResponseWriter, request *http.Request, err error) {
 		responder.
 			Respond(request).
 			Handle(writer, request)
+
+		return
 	}
 
-	Failed(err).Handle(writer, request)
+	NewProblem(err, http.StatusInternalServerError).
+		Respond(request).
+		Handle(writer, request)
 }
 
 func (handler Handler) ServeHTTP(writer http.ResponseWriter, request *http.Request) {
 	handleError(writer, request, handler(request))
 }
+
+func HandlerFunc(handler Handler) http.HandlerFunc {
+	return http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
+		handleError(writer, request, handler(request))
+	})
+}