Subject: bug#38406: 27.0.50; post-self-insert-hook does not hold its contract in cc-mode derived modes

From: Eli Zaretskii <[email-masked]>
Date: Sun, 01 Dec 2019 20:03:38 +0200

> Date: Sun, 1 Dec 2019 15:58:42 +0000
> From: Alan Mackenzie <[email-masked]>
> Cc: [email-masked]
> 
> Why not use post-command-hook here instead?

I don't know what's Ivan's reason, but I know mine: post-command-hook
runs much more frequently (since self-insert-command's are a small
subset of commands in general), and therefore its use is much more
likely to make Emacs less responsive.  E.g., cursor motion commands
will not call post-self-insert-hook.