Re: missing "/" in value of user-emacs-directory when using --init-directory flag

[Robin Tarsiger <rtt@dasyatidae.com>]

Eli Zaretskii wrote:
>> From: Yilkal Argaw <yilkalargawworkneh@gmail.com>
>>
>> In my configs I use (concat user-emacs-directory "somedirectory or
>> file") to refer to files with respect to emacs. When loading emacs
>> with the option --init-directory this
>> this string is not separated by a backslash since the value
>> user-emacs-directory does not have a backslash on the end of it. This
>> might break previous configs so it should be standardized to contain
>> the same string value in both cases.
> 
> Don't use 'concat' for file names; use expand-file-name instead.

While that's as may be in general, the docstring for user-emacs-directory
(in my Emacs 28.2) states "Note that this should end with a directory
separator." specifically, which I take to be part of the variable contract.
Doesn't that imply that it is Emacs's responsibility to handle that aspect
if setting user-emacs-directory based on a file name that may not satisfy
that predicate?

-RTT