Khalid Al-Ghamdi wrote:
> 1. >>> class k:
> 2. def __init__(self,n):
> 3. return n*n
> 4.
> 5.
> 6. >>> khalid=k(3)
> 7. Traceback (most recent call last):
> 8. File "<pyshell#58>", line 1, in <module>
> 9. khalid=k(3)
> 10. TypeError: __init__() should return None, not 'int'
> Why doesn't this work?
Leaving out the details, for a class A
a = A(...)
is essentially a shortcut for
a = A.__new__(A, ...)
a.__init__(...)
__new__(), not __init__() determines what value is bound to the name a.
> And is there way to have an
> object immediately return a value or object once it is instantiated with
> using a method call?
You can write your own implementation of __new__(), but that is expert area
and hardly ever needed. When you aren't interested in the class instance you
shouldn't create one in the first place, and use a function instead:
def k(n):
return n*n
khalid = k(3)
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