[asdf-devel] [RfC] default value for *central-registry*

[Daniel Herring]

On Wed, 23 Sep 2009, Gary King wrote:

>> Would anyone mind ASDF coming with an additional default value of
>> ~/.asdf/systems/?
>
> That does seem like a reasonable default for *nix. Is there an
> analogous spot for Windows / cygwin? Can we use, e.g.,
>
> (merge-pathnames
>    (make-pathname :directory '(:relative ".asdf" "systems")) (user-
> homedir-pathname))

Yes, user-homedir-pathname gives a reasonable value for all the 
implementations I've tested on linux, mac, and windows.

Regarding Tobias's question, if CL/ASDF take off, I think people will want 
more than one default location.  On a unix machine, they might be 
/usr/asdf, /usr/local/asdf, and ~/.asdf.  On Windows, they might be 
C:\asdf, C:\Windows\asdf, and $HOME\asdf (I forget the exact $HOME 
variable name right now).

As Faré pointed out, these should be specified through a site-specific 
configuration rather than being hard-coded into ASDF.  Such configuration 
might involve querying an environment variable or reading a config file 
from a known location (that's how most shells set these environment 
variables).

If reading config files, the two major conventions I know are
- read the global config, then the user config, possibly overwriting settings
- read the first available config file, trying the user config then the global config

Later,
Daniel