Lawrence D'Oliveiro a écrit : > In message <[EMAIL PROTECTED]>, Carsten > Haese wrote: > >> On Thu, 2007-10-04 at 11:11 +1300, Lawrence D'Oliveiro wrote: >> >>> In Python, all names _are_ variables. They are not "bound" to objects. >>> The value of os.path is a pointer. >> No. "os.path" refers to the object that's known as the "path" attribute >> of the object known as "os". That object, in turn, is a module. > > No, it's a variable. It just happens to contain a pointer to a module.
Lawrence, you should have a look at CPython's source code. And at other implementations too. Python's "variables" *really* are name/object pairs - most of the time key/value pairs in a dict. The name itself is just that : a name. It doesn't "contains" anything, it's *not* a label for a memory address, it's *only* a name. >>> It's implemented as a pointer, >> While it is true that namespaces are implemented in CPython as >> collections of pointers to PyObject structures, that's an irrelevant >> implementation detail. I doubt that they are implemented as pointers in >> Jython, PyPy, or IronPython. > > I'll bet they are. Since Java doesn't have pointers, you lost your bet. >>> it has all the semantics of a pointer. >> No, it doesn't. A pointer means the physical address of a memory >> location, which implies that you can overwrite that memory location. Can >> you do that in Python? > > Yes. Look up the definition of "mutable objects". I think Carsten knows this definition. But it has nothing to do with "overwriting a memory location" - like you could do in C using pointers. -- http://mail.python.org/mailman/listinfo/python-list
