PEP0238 lament

Steve Horne sh at ttsoftware.co.uk
Mon Jul 23 14:50:50 CEST 2001


On Mon, 23 Jul 2001 01:08:03 -0400, "Tim Peters" <tim.one at home.com>
wrote:

>[Tim]
>> Of course, but computer numerics is a massive exercise in picking the
>> general rules you want to preserve at the expense of others,
>> and trading all that off against pragmatics too.  Not losing information
>> silently is also a Very Good General Rule, and even 745 binary fp
>> arithmetic is better at meeting that one than current "/".
>>
>
>[Donn Cave]
>> So would it make sense to also change the >> and << operators to
>> rotate shift?  I mean, I sure wouldn't find that more useful, but
>> it does conserve information that the current shifts lose.
>
>First explain what bitstring operations have to do with computer numerics.

Donn didn't claim any such relationship - Tim said that not losing
information is a very good *GENERAL* rule and Donn followed that logic
through quite effectively.

>You may as well as complain that, e.g., "del a[i]" loses information too.
>Well, of course it does -- that's its purpose.  Same thing with >>.  << does

The same applies to integer division - it is an inherently many-to-one
information-losing operation unless you include the remainder as part
of the result.

-- 
Steve Horne
Home : steve at lurking.demon.co.uk
Work : sh at ttsoftware.co.uk



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