[Python-ideas] Wild idea about mutability

[Sven R. Kunze]

On 07.06.2016 15:24, Rob Cliffe wrote:
>
>
> On 06/06/2016 11:44, Sven R. Kunze wrote:
>>
>>
>> Thinking this further, __init__ would be the only function to change 
>> the state of an immutable object. Once created, it will never change. 
>> Immutable also implies hashability IMHO. Moreover, immutable object 
>> would not be allowed to query data from global/external variables as 
>> those can change and would change the observable state of the object 
>> without the object noticing. So, the allowed way of creating a state 
>> for an immutable object would be using a new container as you did (by 
>> defining self._cache) and store immutable objects only there. Would 
>> this make sense?
>>
>> Sven
> That would be one viable design.
> But aren't there use cases for initially creating an object as 
> mutable, then at some point "freezing" it by changing the mutable flag 
> from True to False?
> (Obviously the converse would not be allowed.)

Object freezing sounds like a crazy dynamic idea.

Unfreezing would be even crazier.


I think that would be even better than a static mutable flag. I like 
that. :)


Sven