Re: Why doesn't this method have access to its "self" argument?

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From	Peter Otten <__peter__@web.de>
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Subject	Re: Why doesn't this method have access to its "self" argument?
Date	Thu, 19 Nov 2015 19:00:15 +0100
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Robert Latest via Python-list wrote:

> I found a workaround using a wrapper method which calls a C function,
> passing the instance as a separate argument. It works, and I cannot see
> any disadvantage. It's just not as elegant as I'd like it to be, and I
> don't understand WHY the C "method" doesn't receive a pointer to the
> Python instance. Maybe somebody can clarify.

I don't know much about the C-implementation side, but functions written in 
Python are also descriptors. Given

def f(self): pass

class A(object):
    m = f
    c = abs
    v = 42

a = A()

a seemingly simple attribute access

m = a.m      # m is now a bound method

invokes f.__get__(a, A) under the hood while

m = a.c
assert m is abs

just returns the function (abs in the example) the same way it returns any 
other value:

v = a.v
assert v == 42

Thread

Why doesn't this method have access to its "self" argument? Robert Latest <boblatest@yahoo.com> - 2015-11-19 16:13 +0000
  Re: Why doesn't this method have access to its "self" argument? Chris Angelico <rosuav@gmail.com> - 2015-11-20 04:34 +1100
  Re: Why doesn't this method have access to its "self" argument? Peter Otten <__peter__@web.de> - 2015-11-19 19:00 +0100
  Re: Why doesn't this method have access to its "self" argument? dieter <dieter@handshake.de> - 2015-11-20 08:18 +0100

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