Why do only callable objects get a __name__?

John Ladasky john_ladasky at sbcglobal.net
Mon Nov 18 22:02:26 CET 2013


On Monday, November 18, 2013 12:43:28 PM UTC-8, Ian wrote:
 
> Classes and functions are frequently kept in module namespaces, where
> they are known by a specific name.  The intent is that the __name__
> attribute should match that name by which it is commonly referred.
> 
> 
> 
> Specific instances are not typically widely referred to by set names
> 
> in this way.  They are more commonly stored in variables that are used
> 
> to hold a wide variety of objects.
> 
> 
> 
> In the namedtuple example that you give, it seems that you would want
> the names of all instances of the ANamedTuple class to be the same
> "ANamedTuple", and I really don't see what the purpose of giving them
> all the same name would be.

I am implementing a state machine.  The outputs of the various states in the machine have variable contents.  I started by making dictionaries for each state output, but I soon tired of the bracket-and-quote-mark syntax for 
referring to the contents of these state output dictionaries.  That's why I am switching to named tuples.  It doesn't affect the __name__ issue, since dictionaries also cannot be called.

I want to capture the names of the executed states in a record of the state machine's history.  This information is already encoded in the namedtuple's type.

> > 2. If I created a superclass of namedtuple which exposed type(namedtuple).__name__ in the namespace of the namedtuple itself, would I be doing anything harmful?
>  
> Probably not.  

I just thought I would ask.

> But why not just invent your own name attribute rather
> than shadow the one that Python designates for classes and functions?

I will never write to this attribute, only read it.  And since the information I want is already there (albeit in a strange place), I am inclined to use it.



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