[bug#41949] [PATCH 3/5] guix: Add gerbil-build-system

[edk@beaver-labs.com]

Ludovic Courtès writes:

> Edouard Klein <edk@beaver-labs.com> skribis:
>
>> * guix/build-system/gerbil.scm: New file.
>> (%gerbil-build-system-modules): New variable.
>> (gerbil-build): New variable
>> (gerbil-build-system): New variable
>>
>> * guix/build/gerbil-build-system.scm: New file.
>> (%standard-phases): New variable.
>> (gerbil-build): New variable.
>
> [...]
>
>> +;; Gerbil's build system and package management is documented at
>> +;; https://cons.io/guide/package-manager.html
>> +;; https://cons.io/guide/build.html
>> +;; https://cons.io/guide/env-vars.html
>> +;;
>> +;; The compiler is writing its output in the directory
>> +;; pointed to by GERBIL_PATH (or ~/.gerbil by default).
>> +;;
>> +;; Every package is supposed to have a build.ss script
>> +;; whose default action (when called with no argument)
>> +;; is to compile the package.
>> +;;
>> +;; The GERBIL_LOADPATH env variable tells gerbil's runtime
>> +;; where it can find its loadable code.
>> +;;
>> +;; GERBIL_HOME tells gerbil where to find its runtime
>> +;; and standard library
>> +;;
>> +;; This build system therefore just
>> +;; - makes GERBIL_PATH point to the output directory in the store,
>> +;; - makes GERBIL_LOADPATH point to the lib subdir
>> +;; of all the gerbil inputs,
>> +;; - calls ./build.ss,
>> +;; - wrap any executable with GERBIL_LOADPATH set the the lib
>> +;; subdir of all the gerbil inputs plus the lib subdir
>> +;; of the current package's output, and with GERBIL_HOME
>> +;; set to the lib directory of the 'gerbil' input
>> +
>> +(define (loadpath inputs)
>> +  (string-join (map (match-lambda
>> +                      ((_ . path)
>> +                       (string-append path "/lib")))
>> +                    ;; Restrict to inputs beginning with "gerbil-".
>> +                    (filter (match-lambda
>> +                              ((name . _)
>> +                               (string-prefix? "gerbil-" name)))
>> +                            inputs))
>> +               ":"))
>
> Shouldn’t ‘GERBIL_LOADPATH’ be in ‘native-search-paths’ of Gerbil, just
> like ‘GUILE_LOAD_PATH’ for Guile?
>
> In that case, you wouldn’t need this procedure.  Perhaps, you’d need to
> adjust the convention, though, so that libraries are installed to
> lib/gerbil/ instead of lib/gerbil-* (not strictly necessary because the
> search path mechanism accepts regexps, as used for XML_CATALOG_FILES,
> but somewhat “nicer” IMO).
>
> Thoughts?

I saw native-search-paths in the sources but did not understand its use
and instead copied the python and golang build systems with which I was
more familiar. What you're proposing sounds better than what I've done.

>
> We’d also need an item in doc/guix.texi under “Build Systems”.

Of course.

>
> Please let us know if you cannot work on it in the foreseeable future.
> I might be able to make these changes if they make sense to you.

I'd like to try, but it may take a while :)

>
> Thanks,
> Ludo’.

Thank you for reviewing the patches :) I'll send an update ASAP, maybe
around october.

Cheers,