Converting Python code to C/C++

[Neuruss]

On 23 jun, 12:49, Kurt Smith <kwmsm... at gmail.com> wrote:
> On Mon, Jun 22, 2009 at 9:49 PM, Andras
>
>
>
>
>
> Pikler<Andras.Pik... at students.olin.edu> wrote:
> > Hi!
>
> > Short: I need to turn a Python program that I (mostly) wrote into C code,
> > and I am at a loss.
>
> > Long: I’m doing research/programming for a professor, and we are working
> > with MIDI files (a type of simple music file). The research deals with
> > generating variations from a musical melody; currently, my Python code uses
> > a Python midi package I found online to read the notes in question from a
> > midi file, about 350 lines of my own code to generate a variation based on
> > these notes and the professor’s algorithms, and finally the package again to
> > write the new melody to another midi file.
>
> > Now, my professor would like to have this exact code in C/C++, as she
> > believes C is more compatible with MATLAB, and wants the code to be
> > available in multiple languages in case a programmer works for her in the
> > future who knows C but not Python. While I know a tiny bit of C (emphasis on
> > the tiny), I would much prefer if there were some sort of automatic compiler
> > I could use to turn my Python code into C than taking a week or two or three
> > to learn the minimum I need about C, find a way to access MIDI files in it,
> > and rewrite all of my code.
>
> > After some googling, I found and tried Shedskin, but it doesn’t work, as the
> > Python midi package I’m using uses modules which Shedskin does not support.
> > Otherwise, I haven’t found much. Is there anything out there to help me do
> > this? If not, from anyone who has experience in this regard, how daunting
> > should I expect this to be?
>
> Taking on C from a cold start and being able to handle the ins and
> outs of interfacing with Python isn't something that's feasible in
> 'two or three weeks'.  Here are a couple of options -- take 'em or
> leave 'em:
>
> 1) Put the code in Cython:http://www.cython.org/ (full disclosure:
> I'm doing a GSoC project with Cython).  It will convert pretty much
> any python code into C code (even closures are supported in the most
> recent version, I think), and the C code can then be compiled into an
> extension module.
>
> The only problem with the above is the C code isn't, at first blush,
> easy to read.  Nor is it supposed to be changed by the user.  So that
> leads us to option...
>
> 2) Write the core functionality in C yourself, and then wrap those C
> functions in Cython.  You'll want to take a look at the documentation:
>
> http://docs.cython.org/
>
> and, more specifically on wrapping C code:
>
> http://docs.cython.org/docs/external_C_code.html
>
> I don't think you'll be able to avoid learning C, though.
>
> Kurt

There's another (very good) option: Try shedskin http://code.google.com/p/shedskin/
.
Shedskin can compile a whole program or part of it as an extension
module.
It translates python code to c++ and compiles it.

The good thing is that you don't have to know anything about c or c++.
You simply have to restrict your coding style a little bit to make it
explicitly static.
For example: if you declare a = 5, that means that "a" is an integer,
so you cannot then change it to a string (a = "hello", won't work).

Luis