On Tue, Mar 8, 2016 at 2:54 AM, Tony van der Hoff <t...@vanderhoff.org> wrote: > I thought I understood this, but apparently not: > Under py3: > > 1. "import tkinter" imports the whole module into the name space. Any access > to names therein must be prefixed with the module name. > ie top = tkinter.Tk() > But tkinter.messagebox.showwarning() errors with "module has no attribute > 'messagebox'"
Your description is of a general module, but tkinter is actually a package. Packages are slightly different, in that their modules might not be loaded automatically. You can also do this: import tkinter.messagebox which is a syntax that works ONLY with packages. [1] > 2. "from tkinter import *" loads the name space from the module into the > program name space. No need to prefix the module name onto the attribute > name. Pollutes the name space, but makes typing easier. > ie top = Tk() > But messagebox.showwarning() still errors. > > I imagined that the "*" form implied "load the lot". Evidently, my > understanding is lacking. Will somebody please put me straight, or give me a > reference to some definitive documentation? Sorta-kinda. The star import means "load all the obvious names". Even with non-package modules, it won't always import everything - if there's a list of names in __all__, only those names will be imported. Generally, this means you don't get nested module references (eg because a module did "import sys"), but it can do anything else as well. The documentation should tell you what you need to import to make something work. In this case, I would guess that "import tkinter.messagebox" or "from tkinter import messagebox" would be the recommended way to use this module. ChrisA [1] Modulo os.path, which is done by injection. Ignore that. -- https://mail.python.org/mailman/listinfo/python-list
