func (h handler) Stop(ctx *Context) {
	ctx.Stopped = true
	h.next(ctx)
}
Stop stops the middleware call chain with a custom Context
package context
type HandlerCtx func(*Context)
type HandlerFunc func(*Context, Handler)
type Handler interface {
	Next(*Context)
	Stop(*Context)
	Error(*Context, error)
}
type handler struct {
	next HandlerCtx
}
func NewHandler(fn HandlerCtx) Handler {
	return handler{once(fn)}
}
func (h handler) Next(ctx *Context) {
	h.next(ctx)
}
func (h handler) Error(ctx *Context, err error) {
	ctx.Error = err
	h.next(ctx)
}