Hi Ron:
Thank you for writing me a personal email! Time is our most valuable asset
and I appreciate you giving me some of yours.
Though you didn't answer my question of what namespace to put CELL
in, I understand why. Hopefully I will not be committing a gross
oversimplification when I say that I hear you saying two things:
1. don't re-invent the wheel
2. don't bundle stuff together
As to the first point:
* Configuration. App::CELL's configuration model is inspired by Request
Tracker. An App::CELL configuration file is actually a Perl module (written
as a series of calls to a 'set' function) that is loaded using 'require'.
Not only does this leverage Perl itself to do the parsing -- it provides
great flexibility when it comes to defining configuration parameter values:
they can be scalars, or they can be references to anonymous arrays,
hashes, or subroutines.
Maybe there's already a Config:: module that takes this approach, and I'm
just not aware of it?
* Error-handling. I was inspired by brian d foy's article "Return
error objects instead of throwing exceptions"
http://www.effectiveperlprogramming.com/2011/10/return-error-objects-instead-of-throwing-exceptions/
Though my implementation is slightly different than brian's, I share
his reluctance to get into exception-throwing in Perl. App::CELL
provides a generic status class (which is i18n-able, since it inherits
from the message class). Functions can (but are not required to) return
this status object on both success and failure. On success, the status is
set to OK and the return value can be retrieved via a "payload" method. On
failure, the status is set to a "non-OK" value and the error text
(in the user's
preferred language -- could even be "Australian English" :-) via a "text"
method. Functions are then called like this:
my $status = function_call( .. args ..);
return $status unless $status->ok;
my $result = $status->payload;
When an error occurs, it "bubbles" back up the stack and can be handled
wherever convenient.
Can you point me to an existing module that does this?
* Localization. Just today I "discovered" GNU gettext (and libintl-perl),
which is clearly far superior to my first attempt at an i18n framework
for Perl. No questions there.
* Logging. App::CELL implements a simple logging mechanism (Log::Fast-
based) that is integrated with CELL::Message objects. You are right that
this could be perceived as an attempt to force people to use my logging
mechanism instead of their preferred way. On the other hand, the
configuration, error-handling, and i18n functions _need_ to log. So I
guess I will need to provide a way for folks to overlay App::CELL's
logging functions with their own.
As to your second point (bundling). I will follow your suggestion and think
about how I could enable people to use individual components. This is
already possible with the current version of Api::CELL -- just not
particularly convenient.
Thanks again for sharing your thoughts and for taking the time to consider
mine!
Nathan
On Fri, Jan 31, 2014 at 12:25 AM, Ron Savage <r...@savage.net.au> wrote:
> Hi Nathan
>
> Thanx for reading the advice re naming modules, even if a little late!
>
> There are a wide range of modules on CPAN handling issue such as yours does,
> and tying them together is not the way many of us work.
>
> For instance, I already use config modules, logging modules, etc, and have a
> policy of not adopting a module which forces me to adopt several such things
> just to get the feature I want.
>
> In the short term you can simply delete CELL via the PAUSE web interface.
>
> Then, I strongly suggest you have a think about such matters before deciding
> what to do next.
>
> There is of course no reason you'd like my way of doing things, but just for
> the record my choices are:
>
> o Config::Tiny (and if that's insufficient, Config::IniFiles)
>
> Yes, there's a vast array of config modules on CPAN. No-one needs them all,
> but we all need a good one.
>
> o Log::Handler
>
> Correspondence will not be entered into :-).
>
> o Try::Tiny, perhaps combined with Throwable::Factory
>
> The latter is written by Toby Inkster, which is always a good sign.
>
> o Etc.
>
> Cheers
>
> --
> Ron Savage
> http://savage.net.au/
