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Like c enumeration in python3 [ERRATA]


On 3/22/2020 11:37 PM, DL Neil via Python-list wrote:
> On 23/03/20 3:32 PM, Paulo da Silva wrote:
>> ?s 02:18 de 23/03/20, Paulo da Silva escreveu:
>>> Hi!
> 
> Ol?,
> 
> 
>>> Suppose a class C.
>>> I want something like this:
>>>
>>> class C:
>>> ????KA=0
>>> ????KB=1
>> ????KC=2
>>> ????...
>>> ????Kn=n
>>>
>>> ????def __init__ ...
>>> ??????? ...
>>>
>>>
>>> These constants come from an enum in a .h (header of C file).
>>> They are many and may change from time to time.
>>> Is there a way to somehow define them from inside __init__ giving for
>>> example a list of names as strings?
>>> There is an additional problem: C is not recognized inside __init__!
> 
> 
> Please read the PSL docs carefully, because Python's enums seem to 
> differ from those in other languages - sometimes in significant ways, 
> and sometimes in a subtle manner!
> 
> 
> I have been asking similar questions recently - particularly wanting to 
> (also) use the "strings", because of the effort of upgrading many 
> modules of code at the same time (the manual, or was it the PEP(?) 
> refers to the need to upgrade the PSL to use enums, and to the effort 
> that might cost - I suggest there has been little/v.slow take-up, but 
> then keeping the PSL updated is a subject of a great many conversations, 
> elsewhere).
> 
> Python's enums cannot be changed. Once set, C.KA cannot be changed to 1 

I am not sure what you are saying.  The OP's class is not an enum in the 
enum module sense.  Class attributues are usually mutable.

 >>> class C:
	K = 0

	
 >>> C.K = 1
 >>> C.K
1


-- 
Terry Jan Reedy