[Python-Dev] Issue10403 - using 'attributes' instead of members in documentation (original) (raw)

Michael Foord fuzzyman at voidspace.org.uk
Tue Jun 28 17:35:38 CEST 2011

On 28/06/2011 16:23, Terry Reedy wrote:

On 6/28/2011 7:51 AM, R. David Murray wrote:

Also, instances can have methods as instance attributes. Functions that are instance attributes do not act like methods (instance.func() does not automagically turn instance in the first arg of func) and have never, to my knowledge, been called methods. In Python 2, they are not wrapped as methods whereas functions attached to classes are. So-called 'staticmethods' are not really methods either, but are class function attributes that are just functions and not treated as methods. The decorator that negates normal method treatment could/should have been called 'nonmethod'. Using 'function' is its generic 'callable' sense ... Method: a class function attribute that in its intended and normal use automagically turns the object it is called on into its first arg. 'Method' is a useful and needed subcategory of class attribute precisely because of this behavior. Instance method: a class function attribute that is (normally) called on instances of the class or subclasses.

So what is the difference between "Instance method" and "Method" above? Is it just that "Method" is broader and includes class methods and bound methods?

If anyone said "instance method" to me I would assume they meant bound method. (A normal method fetched from an instance.)

All the best,

Michael

Class method: a class function attribute that is (normally) called on the class or subclasses.

Bound method: a method that has already has the first-arg object bundled with it, so that it can be used as a normal (partial or curried) function. Except for 'classmethod', which was added later, these have been the meanings as I understood them since at least Py 1.4, 15 years ago, and they are exactly what one needs to know to use Python. Any object can be an attribute. However, function attributes of classes normally get special 'method' treatment which alters the meaning of syntax.

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