[Python-Dev] Breaking undocumented API

[Hrvoje Niksic]

On 11/10/2010 05:12 AM, Stephen J. Turnbull wrote:
> But these identifiers will appear at the module level, not global, no?
> Otherwise this technique couldn't be used.  I don't really understand
> what Tres is talking about when he writes "modules that expect to be
> imported this way".  The *imported* module shouldn't care, no?

I think he's referring to the choice of identifiers, and the usage 
examples given in the documentation and tutorials.  For example, in the 
original PyGTK, all identifiers included "Gtk" in the name, so it made 
sense to write from pygtk import * so you could spell GtkWindow as 
GtkWindow rather than the redundant pygtk.GtkWindow.  In that sense the 
module writer "expected" to be imported this way, although you are right 
that it doesn't the least bit matter for the correct operation of the 
module itself.  For GTK 2 PyGTK switch to "gtk.Window", which 
effectively removes the temptation to import * from the module.

There are other examples of that school, most notably ctypes, but also 
Tkinter and the python2 threading module.  Fortunately it has become 
much less popular in the last ~5 years of Python history.