'This class' and 'this function'

Sometimes, when defining a class, the need to refer to this class arises. One could use the class name, but there is the possibility that the class name can be bound to a different object later. The file thisobj.py (download) implements a bindclass decorator which, when decorating a method, binds its first parameter to the class it is defined in.

Using bindclass

>>> class Foo(Object):
...     @bindclass
...     def foo(this_class, self):
...         return this_class, self
...
>>> class Bar(Foo):
...     @bindclass
...     def bar(this_class, self):
...         return this_class, self
...
>>> f = Foo()
>>> b = Bar()
>>> f.foo()
(<class '__main__.Foo'>, <__main__.Foo object at 0x61270>)
>>> b.foo()
(<class '__main__.Foo'>, <__main__.Bar object at 0x56f50>)
>>> b.bar()
(<class '__main__.Bar'>, <__main__.Bar object at 0x56f50>)
>>>

Using bindfunction

>>> def fac(n):
...     if n == 0:
...             return 1
...     else:
...             return n * fac(n-1)
... 
>>> fac(10)
3628800
>>> fact = fac
>>> fact(10)
3628800
>>> fac = 'foobar'
>>> fact(10)
Traceback (most recent call last):
  File "", line 1, in 
  File "", line 5, in fac
TypeError: 'str' object is not callable
>>>

>>> @bindfunction
... def factorial(this_function, n):
...     if n > 0:
...         return n * this_function(n - 1)
...     else:
...         return 1
... 
>>> factorial(15)
1307674368000L
>>> fac = factorial
>>> fac(15)
1307674368000L
>>> factorial = 'foobar'
>>> fac(15)
1307674368000L
>>>