On Sun, 29 May 2011 16:19:11 -0400 Henry Olders <henry.old...@mcgill.ca> wrote:
> > def fnc2(c): > > c = c[:] > > c[1] = 'having' > > return c > > Thank you, Wolfgang. That certainly works, but to me it is still a > workaround to deal with the consequence of a particular decision. > From my perspective, a function parameter should be considered as > having been assigned (although the exact assignment will not be known > until runtime), and as an assigned variable, it should be considered > local. > > Henry This has nothing to do with function parameters and everything to do with what a "variable name" actually means. You can get the same effect with only globals: >>> x=[1,2,3] >>> y=x >>> x.append(7) >>> y [1, 2, 3, 7] Why in the world does "y" end with 7, even though it was appended to "x"? Simple: because "x" and "y" are two names for the same list, as Henry explained. No functions involved, no locals, no parameters, no scoping. Again, if "y=x" were instead "y=x[:]" then the output would be "[1,2,3]" because "y" would refer to a copy of the list rather than the same list. Chris -- http://mail.python.org/mailman/listinfo/python-list
