On Thu, Jul 31, 2008 at 1:59 PM, Nikolaus Rath wrote: > If it is just a matter of different rendering, what's the reason for > doing it like that? Wouldn't it be more consistent and straightforward > to denote builtin types as classes as well?
Yes, and in Python 3, it will be so: >>> class myint(int): pass ... >>> int <class 'int'> >>> myint <class '__main__.myint'> The reason the distinction is made currently is that before Python 2.2, "types" were built-in (or C extension) classes, and "classes" were Python classes; it was not possible to subclass built-in types. That "classic" style of classes are still supported in Python 2.2 and above (but not in Python 3), by not inheriting from object or any other built-in. However, for new-style classes, the only distinction is in the repr. >>> class classic: pass ... >>> class newstyle(object): pass ... >>> type(classic) <type 'classobj'> >>> type(classic()) <type 'instance'> >>> classic.__class__ Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: class classic has no attribute '__class__' >>> classic().__class__ <class __main__.classic at 0x64e70> >>> >>> type(newstyle) <type 'type'> >>> type(newstyle()) <class '__main__.newstyle'> Further reading: http://www.python.org/download/releases/2.2.3/descrintro/ http://svn.python.org/view?rev=23331&view=rev http://bugs.python.org/issue2565 -Miles -- http://mail.python.org/mailman/listinfo/python-list
