Re: [myhdl-list] Signal getattr and setattr

[Jan D. <ja...@ja...>]

Christopher L. Felton wrote:
> Jan Decaluwe wrote:
>> Christopher L. Felton wrote:
>>> Jan Decaluwe wrote:
>>>> Chris:
>>>>
>>>> I don't have a lot of time these days (moving to new house) but
>>> No problem, this is not a bug often encountered and I have a work around 
>>> for accessing the "contained" objects attributes/properties.  Enjoy 
>>> moving to the new house!
>>>
>>>> did your patch mean that __slots__ is the problem?
>>> I don't believe __slots__ is the problem.  And you do get the 
>>> performance increase from __slots__ but I don't know how much.
>>>
>>> I believe the issue is how the copy works.  The copy tries to access 
>>> variables before they exist?  I don't know the exact mechanism of the 
>>> copy but that appears to be the issue.
>>>
>>> By adding an attribute read in __init__ before it is set, a similar 
>>> failure occurs.  Example first line of __init__ print self._val.
>>>
>>> At this point two options would be remove __getattr__ or add __copy__ 
>>> and __deepcopy__ to return a new instance and set attributes manually.
>> That seems the good solution.
>>
>> Of course, how easy it is depends on what "copying" means. The way I
>> think about it, it seems trivial: simply create a new signal with the
>> same initial value. This would create a new signal that, in the same
>> context, would behave identically to the original, but with for the
>> rest all separate data structures internally.
>>
>> That is what a "copy" is to me, but what about your application?
> 
> Yes, copy to me means the same.  Same as the copy implementations in 
> intbv?  Adding the __copy__ and __deepcopy__ makes sense otherwise it is 
> passed to the "val" copy implementation.

Then I think the proper way is for the copy functions to
return Signal(self._init).


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