[Texmacs-dev] Re: Compiling TexMacs on OSX

[Henri Lesourd]

Abdelrazak Younes wrote:

> Henri Lesourd wrote:
>
> > Abdelrazak Younes wrote:
> >
> > > In the case of Qt plugins the only thing to take care of is that the 
> > > plugin are develop with a version lower or equal than the one with 
> > > which TeXmacs was compiled, that's all.
> > That's the job of the plugin implementor, not ours.
>
>
> Well, please let me say that sorry but, even if TeXmacs is very good, 
> I don't think you'll get a lot of external plugin implementors if any.

If the people see TeXmacs as a valuable starting
point for the project they want to do, yes.

By the way, I myself received a salary during four
years precisely because such a plugin project.


> For this to happen you'll have to gain a lot of market share (which I 
> don't see happening in the foresable future).

You don't need *a lot* of projects to be in a situation
where you have to work on these issues.


> So, if someone really is interested in adding a feature to TeXmacs, 
> I'll bet it's just easier to try to put in there directly.
Definitely not: most of the time, the patch would
be rejected, except if the author is extremely
careful in following the coding style.

This being said, there are parts of the codebase
which are more difficult than others.

In such a situation, the lack of extensions of TeXmacs
becomes a self-fulfilling prophecy, but as a matter of
fact, it is mainly due to the lack of componentization
of the software.


> > > So, if this is the only reason for the glue library, I don't see a 
> > > very big added value.
> > The added value is that people can develop new widgets
> > independently, and load these widgets inside TeXmacs
> > *without the need of recompiling TeXmacs*.
>
>
> You can do that with C++, I am 100% sure of this.
Well, check your documentation. Mine says:
[[
C++'s greatest weaknesses in this area is the lack of
a C++ ABI on some platforms and the lack of a native
notion of a dynamically linked library.
]]
 B. Stroustrup (interview): C++: past, present, and
 future. Frontier Channels, September 2006.


Thus yes you can do it: but only if you wrap your C++
classes behind a C API.


> > Thus the mechanism is 100% dynamic, and without a glue
> > library which exports only a C API, it would not be
> > possible to do things this way (otherwise, recompiling
> > TeXmacs from source would be required each time you
> > modify your plugins).
>
>
> I still don't buy this argument, the C++ ABI has been stable for a 
> number of years already and many C++ applications support old plugins 
> without problem. Provided that you don't change the API the plugins 
> should continue to run just fine if TeXmacs is upgraded.
Excuse me, but when I look at the dl_open() functions, I
see absolutely *nothing* which would allow me to fetch a
class contained inside a .so and call its constructor and
methods.

Thus what you say seems interesting, but currently, it
is a little bit too much fuzzy to be useable information.