By "standard features" I mean line numbering, format on save, auto-parens, etc. The current situation have these downsides: 1. complexity in configuration. Some of the packages that provide these features also provide toggling command,e.g. toggle-line-number or autoparens-mode.However, some __are not__, e.g. format on save.Toggling such feature requires users to implement their own commands.What's worse, they need to implement a toggling commandfor __each and every__ language. 2. problem when other package needs to toggle For example, I wrote a package that needs to temporarily disable auto-parens.I have to write code that handles electric-pair-mode, autoparens and paredit.Further more, byte compiler is not happybecause I was referring functions it doesn't know about. Here is my thought about it: Provide toggle commands and corresponding hook for each of these features.Feature providers add their toggle function to the proper hook.When user toggles on/off, the toggle command runs each functionin the hook with an aregument indicating that user is turning on or turning off,maybe t and nil. How do you think? Have there been similar discussions? Sincerely, Yuan