bug#74532: with-extensions does not add native extensions to the load path

["Ludovic Courtès" <ludo@gnu.org>]

Hi,

Tomas Volf <~@wolfsden.cz> skribis:

> The documentation for `with-extensions' says:
>
>> In the same vein, sometimes you want to import not just pure-Scheme
>> modules, but also “extensions” such as Guile bindings to C libraries
>> or other “full-blown” packages.

It’s not just bindings but also pure Scheme libraries like Guile-JSON.

> However it does not actually add those C libraries into
> (guile-extensions-path), which means that trying to actually use a
> library imported this way will lead to an error.

[...]

>    190:25  1 (load-foreign-library _ #:extensions _ #:search-ltdl-library-path? _ # _ # _ # …)
> In unknown file:
>            0 (dlopen "libguile-yamlpp.so" 1)
>
> ERROR: In procedure dlopen:
> In procedure dlopen: file "libguile-yamlpp.so", message "libguile-yamlpp.so: cannot open shared object file: No such file or directory"

Usually, packages like these (guile-gnutls, guile-git, guile-ssh, etc.)
have their .so absolute file name hard-coded, which sidesteps this
problem entirely.  I recommend doing that for guile-yamlpp as well.

That said, it would probably make sense to arrange for ‘with-extensions’
to set GUILE_EXTENSIONS_PATH.

Ludo’.

PS: Your MUA sets “Mail-Followup-To: bug-guix@gnu.org”, which is kinda
    annoying because that’s the wrong address when replying to a bug.
    :-)