"compile()" portability

[Fredrik Lundh]

Just wrote:

> > I would like to know if executing:
> >
> >    c = compile('a=5\nprint a','<string>','exec')
> >
> > on a Linux box, then pickling+beaming the result on a Windows box, will give
> > me the expecting result:
> >
> > >>> exec(c)
> > 5
> >
> > In other words, does 'compile()' generate platform-dependent code?
>
> If you mean "marshal" instead of "pickle", and use the same (major)
> Python version on both ends, then yes.

to make sure both sites are using the same byte code revision,
check the imp.get_magic() string.

something like this should work:

    code = compile(...)
    data = imp.get_magic() + marshal.dumps(code)

    ...

    magic = imp.get_magic()
    if not data.startswith(magic):
        raise ValueError("cannot run this bytecode")
    code = marshal.loads(data[len(magic):])

(len(magic) is currently 4, and will probably remain so for the
foreseeable 2.X future, but one never knows what happens in
3.X...)

</F>