Better(tm) and Smarter(tm) bash initialization

Intro

Once upon a time, I needed smarter bash initialization scripts. Smarter in a lot of senses. Basically, something that could be handled more easily than a single .bashrc file.
This is my current iteration.

.bashrc: The very beginning

Everything starts from the .bashrc file, as usual. My current version just skips everything else in case it is not run in interactive mode.
Otherwise it passes the control (via source built-in) to the actual initialization code, contained in the .rc file.

.rc: Looping through initialization scripts

This script is run within the very same context as the original (login) shell and loops through the files contained within a cofigurable directory, ${HOME}/.rc.d by default.
All readable files are sourced in the order defined by the current (default) locale.
Unreadable files are simply skipped.
In my example I prefix file names with two digits number to make sure I have proper order of execution. Anything else can also be OK: YMMV.

Some examples

As an example, I have added a few files with some stuff I normally setup for my bash. Just a few notes.

1. I have a fancy prompt setup. It basically is a plain old prompt withing narrow screens (<= 80 columns).
   With wider screens it adds some interesting details: last command timestamp, optional git branch, optional non-trivial return code from previous command, userid and hostname, current path.
2. My locale is setup in my mother language (Italian) but I like to keep error messages in English and old-fashioned ls file sorting (ASCII-based).
3. I try to keep consistent time and date display format via my TIMEFORMAT variable. HISTTIMEFORMAT (history timestamps) and TIME_STYLE (ls time/date output) are defined from there.
4. My own macro names all have a leading comma , (it can also be a colon :) to avoid any command name conflict. Aliases instead have no comma to overrule the corresponding command.
5. pathupdate macro adds directories to the PATH variables if they are not already there. It helps preventing its overgrowth.

Notes

1. You can embedd the .rc file in the .bashrc. You won't gain any noticeable init speedup at the possible cost of lesser flexibility.
2. Those are not script in the "usual" sense as they ar elacking the shebang prologue. This ensures all setup actions happen within the main shell.

References

• Bash Reference Manual
• ls(1)
• shebang