Op 17-08-13 17:01, Steven D'Aprano schreef: > > And here you re-import the name "y" from struct_global. That rebinds the > current module's "y" with whatever value struct_global.y has *now*, > rather than a second (or a minute, or an hour) earlier when the first > import took place. Obviously at some point between the first import and > the second import, struct_global.y must have been reassigned from -1 to > 62. > > This goes to show why global variables are considered harmful, and why > clean, modern program design tries to reduce the use of them as much as > possible. Global variables are too easily modified by, well, *anything*. > The sort of behaviour you are seeing is sometimes called "action at a > distance" -- something, anything, anywhere in your program, possibly > buried deep, deep down inside some function you might never suspect, is > changing the global variable.
I think you are overstating your case. Classes and functions are variables too and in general nobody seems to have a problem with them being global. -- Antoon Pardon -- http://mail.python.org/mailman/listinfo/python-list
