code: func NewPathRecorderMux(name string) *PathRecorderMux {
  	ret := &PathRecorderMux{
  		name:            name,
  		pathToHandler:   map[string]http.Handler{},
  		prefixToHandler: map[string]http.Handler{},
  		mux:             atomic.Value{},
  		exposedPaths:    []string{},
  		pathStacks:      map[string]string{},
  	}
  
  	ret.mux.Store(&pathHandler{notFoundHandler: http.NotFoundHandler()})
  	return ret
  }
docs: // NewPathRecorderMux creates a new PathRecorderMux