Re: %module-public-interface

[ludo@gnu.org (Ludovic Courtès)]

Hi Ian,

Ian Hulin <ian@hulin.org.uk> writes:

> On 30/03/10 22:52, Ludovic � wrote:

>> Andy Wingo<wingo@pobox.com>  writes:
>>
>>> On Tue 30 Mar 2010 22:56, ludo@gnu.org (Ludovic Courtès) writes:
>>>
>>>>> I'm pretty sure that the submodule thing can be changed without any
>>>>> problem. But it seems that the %module-public-interface is used
>>>>> explicitly, at least by texmacs and lilypond.
>>>>
>>>> How do they use it?
>>>
>>> Linking to the evil empire:
>>>
>>> http://www.google.com/codesearch?hl=en&lr=&q=%25module-public-interface&sbtn=Search
>>> http://www.google.com/codesearch?hl=en&lr=&q=%25module-public-interface+lang%3Ac%2B%2B&sbtn=Search
>>
>> Lilypond does:
>>
>> --8<---------------cut here---------------start------------->8---
>>        mod = scm_call_0 (maker);
>>        scm_module_define (mod, ly_symbol2scm ("%module-public-interface"),
>>                           mod);
>> --8<---------------cut here---------------end--------------->8---
>>
>> Solution: do something like:
>>
>> --8<---------------cut here---------------start------------->8---
>> #ifdef HAVE_SCM_SET_MODULE_PUBLIC_INTERFACE_X
>>    scm_set_module_public_interface_x (mod, mod);
>> #else
>>    scm_module_define (mod, ly_symbol2scm ("%module-public-interface"),
>>                       mod);
>> #endif
>> --8<---------------cut here---------------end--------------->8---
>>
>> (We just need to add that function.)
>>
>
>> TeXmacs does:
> <snip>
>>>> And we could add a ‘public-interface’ slot to ‘module-type’ and have
>>>> ‘module-public-interface’ and ‘set-module-public-interface!’ refer to
>>>> it; for backward compatibility we’d also initialize the
>>>> ‘%module-public-interface’ binding.  How does it sound?
>>
>> Actually the trick wouldn’t work in cases where the
>> ‘%module-public-interface’ binding is mutated, as with Lilypond.
>>
>> Given this and the above examples, I’d suggest dropping that binding
>> completely and sending patches to the Lilypond/TeXmacs people.
>>
>> What do you think?
>
> If you do add scm_set_module_public_interface_x, could you back-port
> it to Guile V1.8.6 and V1.8.7?

We could back-port it to the 1.8 series, but not to the already-released
1.8.7 and 1.8.6.  We’d have to make a 1.8.8 release, but I’m not sure
that would really help anyway since that would force Lilypond users to
switch to that version.

> Those are the lowest versions of Guile the upcoming stable release of
> Lilypond will support.

How about doing #ifdef HAVE_SCM_SET_MODULE_PUBLIC_INTERFACE_X in your
code?

We still have to agree on the change and actually implement it, the
latter being easy. ;-)  When is the new Lilypond release due?

Thanks,
Ludo’.