embedding

[Michael P. Reilly]

vysteric at my-deja.com wrote:
: I've been reading through my docs for hours, and I can't seem to find an
: answer to this.. How do you create an object in the main namespace and
: how do you get the value of an object in the main namespace? Without
: using PyRun*

: thanks

: Patrick

Hi Patrick,

I'm surprised that noone has answered this before now.  You will want
to first import the module, then access attributes of it.

  PyObject *module__main__;
  PyObject *MyName, *whom;

  module__main__  = PyImport_ImportModule("__main__");
  /* try:...except:...*/
  if (module__main__ == NULL)
    return NULL;
  MyName = PyString_FromString("Arcege");

  if (PyObject_SetAttrString(module__main__, "person_name", MyName) == -1) {
    /* an exception */
    Py_DECREF(module__main__);
    Py_DECREF(MyName);
    return NULL;
  }
  Py_DECREF(MyName);

  whom = PyObject_GetAttrString(module__main__, "person_name");
  if (whom == NULL) {
    Py_DECREF(module__main__);
    return NULL;
  }
  PyObject_Print(whom, stdout, Py_PRINT_RAW);
  Py_DECREF(module__main__);

This is roughly equivalent to:
  import __main__
  __main__.person_name = "Arcege"
  print __main__.person_name

I use this a good deal to get access to other modules in my own code.

But, if you mean: "How can I create an object in the global namespace?"
That is slightly different; for this you can use PyEval_GetGlobals().
This returns a dictionary, on which you can then use
PyDict_GetItemString() and PyDict_SetItemString().

  -Arcege