[asdf-devel] Reloading a .asd

[Faré]

On Sun, May 6, 2012 at 3:27 PM, Stelian Ionescu <sionescu at cddr.org> wrote:
> I'm using the elisp snippet below(courtesy of Stas Boukarev with some
> modifications) to reload a .asd file. Is asdf::load-sysdef the best way
> to trigger a reload(but not recompilation) ?
>
Yes, with a catch: IF there's a system in your
central-registry, source-registry, quicklisp registry,
or wherever locate-system will find it,
then that OTHER system will be found by the next find-system,
as called whenever you try to compile it.

So load-sysdef will only help you define a system
that CANNOT be found by locate-system.

What if you want to override what locate-system finds?
Well, then override your source-registry,
by exporting CL_SOURCE_REGISTRY,
or giving an explicit parameter to asdf:initialize-source-registry.
And the system is located by some other hook that has precedence
over the source-registry (e.g. *central-registry*), then
it's your responsibility to properly configure that hook.

> Use case: I want to work on a system that isn't in the ASDF path, it
> being one of the many development trees I have around(e.g. CFFI), so I
> want to be able to say that "this cffi.asd is the CFFI to use during
> this session". Any ideas ?
>
If the session is well-defined enough to have some initial incantation
or configuration file, I would use something like this to set it up:

(asdf:initialize-source-registry
 '(:source-registry
   (:tree "/path/to/overriding/cffi")
   (:tree "/path/to/other/overriding/library")
   :inherit-configuration))

Or, a bit more brutal and old-fashioned:
(pushnew #p"/path/to/overriding/cffi/" asdf:*central-registry*)
(pushnew #p"/path/to/overriding/cffi/uffi-compat/" asdf:*central-registry*)


If you want a 100% answer for a dynamically defined SLIME-directed session,
where whichever .asd file you load incrementally modifies current session,
I'd add another hook in front of asdf:*system-definition-search-functions*,
that remembers whichever .asd you load that way, then calls load-sysdef.
That would be a nice addition to slime's asdf support.

—♯ƒ • François-René ÐVB Rideau •Reflection&Cybernethics• http://fare.tunes.org
To do evil a human being must first of all believe that
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