[Bf-python] Consistency issue

[Willian Padovani Germano]

Hi,

Months ago, Jacques suggested that the better method would be to have tuples
everywhere.  That's not a bad idea, but we had to keep compatibility with
2.25.

Now's a good time to start fixing this where it happens, allowing both cases
(ex: someFunc([f,f,f])  or someFunc(f,f,f) calls).

From: "Michel Selten" <michel.s at home.nl>
(...)
> 3 - Update the setLocation() function to both accept a tuple and a
>     list of values. This would imply that both the following calls
>     are valid in a script:
>     obj.setLocation (0.0, 0.0, 0.0)
>     obj.setLocation ((0.0, 0.0, 0.0))
>
> My personal preference would go to option 3.

I like this one, too.  And you're right, once we "unwrap" a pytuple, it
isn't available for another parsing.  A simple way to solve this:  first
check the size of the PyObject *args parameter.  If the function expects
[f,f,f] or f, f, f, it's simple to decide: the size of 'args' will be either
1 or 3.

Check this method in rgbTuple.c, for example:
------------------------------------------
PyObject *rgbTuple_setCol (BPy_rgbTuple *self, PyObject *args)
{
 int ok;
 float r = 0, g = 0, b = 0;

 if (PyObject_Length (args) == 3)
  ok = PyArg_ParseTuple (args, "fff", &r, &g, &b);

 else ok = PyArg_ParseTuple (args, "|(fff)", &r, &g, &b);

 if (!ok)
  return EXPP_ReturnPyObjError (PyExc_TypeError,
          "expected [f,f,f] or f,f,f as arguments (or nothing)");

 *(self->rgb[0]) = EXPP_ClampFloat (r, 0.0, 1.0);
 *(self->rgb[1]) = EXPP_ClampFloat (g, 0.0, 1.0);
 *(self->rgb[2]) = EXPP_ClampFloat (b, 0.0, 1.0);

 return EXPP_incr_ret (Py_None);
}

---------------------------------

See? PyObject_Length(args) is used before PyArg_ParseTuple, to handle three
cases: "f,f,f" or "|(f,f,f)" == nothing or (f,f,f).

> the deprecation of the old method in a few releases and support the new
> method only after that.

Well, no need to, we can document the better one and let the old still
there, undocumented.

BTW: Ton mentioned he's on a coding spree (ok, not his words).  Our little
corner wouldn't interfere with anything, but even so, I'll wait one or two
days before committing anything.

--
Willian, wgermano at ig.com.br