On Wed, 15 Apr 2020, Chris Muller wrote:

>       But the hash can't always be copied over, so it's a tough decision what
>       the default should be:
>       - if the hash is not copied by default, the lack of rehashing will cause
>       elements to be not found in the affected collections 
>
>       - if the hash is copied, runtime errors will be raised when coping the
>       hash is not possible.
> 
> 
> I think a "lack of rehashing" issue could also occur in the latter case, too, if the target of the become (the argument) was in a identity hashed collection..

Right. #become: doesn't change the identity hashes.


Levente

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