Re: user-controlled load-path extension: load-dir

[Ted Zlatanov <tzz@lifelogs.com>]

On Sat, 5 Mar 2011 11:11:34 -0800 Chad Brown <yandros@MIT.EDU> wrote: 

CB> On Mar 4, 2011, at 7:18 PM, Ted Zlatanov wrote:
>> 
>> By analogy consider some of the software that lets you put a snippet in
>> a conf.d directory, obviously implying that this is convenient for the
>> user.  This is just a sampling from my machine:

CB> Those are all machine-wide configurations.  For that, use site-lisp.

Bazaar has a plugins directory; files in it are automatically activated,
as an example of a user-level facility like this.  Anyhow, my point is
that placing a file in a directory is inherently more modular and
convenient to the user than augmenting a single file.  Do you disagree?

CB> If the user has to go through a set of steps to install and activate a
CB> package, how isn't that what ELPA does?

They are not packages, they are snippets of code.  ELPA requires far
more structure and many more steps.  For what I'm proposing, a lot less
work is required (just a y/n prompt the first time a snippet is found to
ensure it's not placed there maliciously).

On Sat, 5 Mar 2011 23:21:51 -0800 Mike Mattie <codermattie@gmail.com> wrote: 

MM> There are ways to solve the problem you are looking at without wiring more
MM> logic into Emacs. Use the .emacs file as a more sophisticated loader for a
MM> complex configuration when necessary.

I can and do, sure.  I don't think it creates a nice user experience.

MM> I have done this with my Grail project (on EmacsWiki), as has tidyconfig.
MM> I would look at these solutions first before proposing code that has to
MM> be wired into the bootstrap codepath.

Thanks for pointing those out.  Would Grail or tidyconfig work as a core
option on startup (meaning the user doesn't have to install a package,
just customize a boolean)?  Do they handle signing the snippets the
first time they are found?  Can you give us a comparison of them and any
other similar solutions you know?  They have to be GPL and assigned to
Emacs to be included.

MM> There are a number of issues a reliable loader should address:

MM> how does it handle errors ?

MM> how does it handle --batch ?

MM> how does it handle --daemon ?

MM> how simple,transparent,debuggable is the loader code ?

MM> I have not seen any code so far in your proposal unless I accidentally
MM> skipped or deleted a message with it.

I can write the code but haven't seen the need for actual code yet (I
could have just comitted some code to Emacs instead, but find that
option to be antisocial).

I'd rather use something that already exists such as Grail or tidyconfig
that you kindly pointed out.  If you could tell us how any potential
solutions can help answer the questions above, that would be wonderful.
I can look at any solutions and evaluate them if you like.

To answer your questions from my perspective, IMHO a loader should work
like package.el.  IOW, whenever and however package.el is loaded
currently, this loader we're discussing should also be loaded, since
it's effectively a package manager but with snippets instead of
packages.

Ted