Re: bug#19068: Mail file vars aren't derived from customized message-directory

[Kelly Dean]

Lars Ingebrigtsen wrote:
> That's the wrong way to set variables that have other variables that
> depend on them.
>
> Instead say
>
> (setq message-directory "~/mail/")
> (require 'message)

And what if you happened to previously require something that already required 
message? Do you want to require users to always put all their «setq»s before 
all their «require»s, just in case?

Or what if you were already using message mode with the default directory 
settings, but then you decided to change it and customize message-directory 
using Emacs's customization feature, and read the help page that says 
⌜Directory from which all other mail file variables are derived⌝? Would you not 
expect that when you change a top-level directory, the directories under it 
remain under it? After all, that's the way «mv» behaves.