Re: Lisp primitives and their calling of the change hooks

[Eli Zaretskii]

> Date: Fri, 5 Jan 2018 11:41:07 +0000
> Cc: address@hidden, address@hidden
> From: Alan Mackenzie <address@hidden>
> 
>     The "complex primitive" case can be distinguised from the "atomic
>     primitive" case because either the call to `after-change-functions'
>     is missing (i.e. there are two consecutive calls to
>     `before-change-functions'), or in the first call to
>     `after-change-functions', `OLD-LEN' is less then `END' - `BEG' in
>     `before-change-functions'.
> 
> The above leaves unsaid what happens when a "complex primitive" happens
> to call b-c-f and a-c-f as though it were an "atomic primitive".

It also provides no way to know, up front, whether a given primitive
I'm about to call, is one or the other.  IMO, we need some way of
doing that, if we want to document this distinction.