Dennis Lee Bieber wrote:
On Wed, 27 Aug 2008 16:21:03 -0400, RgeeK <[EMAIL PROTECTED]>
declaimed the following in comp.lang.python:
I have a main module doStuff.py and another module utility.py. At the
start of doStuff.py I call
import utility.py
I hope not... import utility no .py
Then I also proceed to initiallize some global variables
Python does not have global variables. Names belong within a module
(or within functions defined within the module).
sName = ""
Then I create a class, some methods etc. In one of the methods I assign
a value to my variable sName. Then I call a function from within
my utility.py file:
utility.makeOne(stuff)
Within my utility.py file, I define the makeOne function. But I want to
use that same global variable "sName" In utility.py I have tried to
indicate that I'm using the global "sName" through the statement:
global sName
The global statement is only used within functions (def blocks) to
indicate that "writes" to the specified name are to modify the MODULE
level version of the name, otherwise a write modifies a function local
version of the name (you don't need global for read-only access of
names, the search for names first looks inside the function, then out to
the module)
But when I go to use the variable it still gives me an error:
NameError: global name 'sName' is not defined
I thought perhaps I need to indicate 'globality' in my main module, so
before I initiallized sName in doStuff.py I added:
global sName
But it doesn't help me. I had this issue before and resolved it by
declaring the variable global in the sub-module utility.py, but then I
needed to reference it in my main module with a prefix:
utility.sName = ""
It's more verbose,and defining globals in a submodule seems backward.
But also, what if I need to access "sName" in another imported module,
say "otherstuff.py"? I would do my "import otherstuff" call in my main
module, but would I have to put an "import utility" into the
otherstuff.py file?
If you really need "globals" the common solution is to create a
module such as "myglobals", define all the shared names within that
module, and import that module where ever you need access to one of the
names. And yes, you will need to qualify all those names with the module
name (though you can do things like:
import myglobals as mg
and then use
mg.somename
instead of
myglobals.somename)
Thanks for the reply. Good to see that approach has broad support :)
I'll do that. I like the idea of a nice short alias for the import to
keep the qualifications brief.
Ross.
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