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Re: Behavior of bitwise ops on unencountered wide characters

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Karl Williamson
July 12, 2017 17:03
Re: Behavior of bitwise ops on unencountered wide characters
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On 07/12/2017 04:50 PM, Sawyer X wrote:
> On 07/11/2017 01:09 PM, Karl Williamson wrote:
>> On 07/10/2017 11:12 PM, Father Chrysostomos wrote:
>>> Karl Williamson wrote:
>>>> I don't yet have a fully formulated opinion on this, but one question I
>>>> would have is "How is this different from division by 0" that people
>>>> seem to deal ok with.
>>> Fatal division by zero is ancient.  Fatalizing bitwise operations on
>>> utf8 breaks stuff.
>>> As I suggested in another thread (I seem to have been ignored), it
>>> would be *much* kinder to users to make it a warning.  (Wide character
>>> in blah blah blah.)  That way users who care can fatalize it, or sup-
>>> press it.  You have the best of all three worlds.
>> I believe I've referred to your suggestion in some thread.  It is the
>> minimum we should do.  And others believe it should be deprecated.
> There is a specific cost here Graham noted. This method is currently
> used to determine if a variable is a number without loading "B", which
> isn't cheap. While it is a simple argument of "users shouldn't care,"
> serializations (like JSON) need to be able to map them to their right
> type. It would be nice if there was a way to do this without B.

It would be good to have some alternative that requires only a cheaply 
loaded, or internal module, something named like "Internals" that 
provides a clear access path for the things we have determined warrant 
it, such as Graham's use case.  He had to explain to me how it worked, 
and he had to explain to Yves as well.  That demonstrates is is 
non-obvious.  When the tools aren't available, people will do clever, 
but non-maintainable things to get what they need.  But it is best to 
furnish the tools when it becomes known that they would be useful.

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