[C++-sig] Pyste: serious bug with --multiple.

[Nicodemus]

Prabhu Ramachandran wrote:

>Hi,
>
>Found a serious bug with Pyste's --multiple option.  It would not mix
>up the declarations and put them in wrong files.  I've attached a
>patch that fixes this problem.
>

Applied, thanks again!

>Generating only one file per --multiple is nice but still has the old
>problem where if I change one interface file I need to wait several
>minutes for pyste (gccxml actually) to regenerate the files.
>Nicodemus suggested that a --xml-cache option would be useful.
>However even with that option you'd generate many xml files and will
>need to keep track of those files etc. 
>

Yes, the idea was that Pyste would generate a xml file for each header 
parsed. Keeping them updated would be the build's system job: when a 
header is modified, it should delete the corresponding xml file, so that 
Pyste would rebuild it.

> Instead I have a much simpler
>approach that will solve much of our problems.
>
> 1. Add a --only-wrap option that will process any number of interface
>    files and will generate the necessary wrapper code and *will not*
>    generate a _main.cpp file.  Further, it will add an extra function
>    to each _interface_name.cpp file that reads something like this:
>
>      void _interface_name_module_init()
>      {
>           Export_SomeClass();
>           Export_SomeHeader_H();
>           // ...
>      }
>
> 2. The --multiple option with the --only-main option will simply
>    create a _main.cpp with something like this:
>
>      void _interface_name_module_init();
>      BOOST_PYTHON_MODULE(module_name)
>      {
>          _interface_name_module();
>          // ...
>      }
>
>    Note that the above does not need to use gccxml at all since it
>    only needs the interface file names.  This should make it possible
>    to selectively compile individual interfaces via --multiple
>    --only-wrap and then generate a _main.cpp separately using all the
>    interfaces very quickly.
>  
>

If that solves your problem, that's fine then. 8)

But I don't see a need for the _interface_name_module_init() function, 
since BOOST_PYTHON_MODULE can call them, and the fact that Base classes 
must be exported first, would make things complicated.

>There are other issues not related to the above also but I won't go
>into them here.
>
>I'm going to go ahead and implement --only-main and --only-wrap on my
>copy of the code here and will submit it to the list if it works
>nicely.  I'll let you folks decide if it goes into CVS or not.
>  
>

Sure thing, I don't see why not. 8)
Let's implement this then, if that solves the problem.

>cheers,
>prabhu
>

Thanks a lot Prabhu. Your efforts in improving Pyste are greatly 
appreciated!

Regards,
Nicodemus.