PEP308: Yet another syntax proposal
Bengt Richter
bokr at oz.net
Tue Feb 11 00:16:42 EST 2003
On Mon, 10 Feb 2003 10:23:11 -0800 (PST), Dave Brueck <dave at pythonapocrypha.com> wrote:
>On Mon, 10 Feb 2003, Aahz wrote:
>
>> In article <YUP1a.3080$SB2.242 at nwrddc03.gnilink.net>,
>> Raymond Hettinger <python at rcn.com> wrote:
>> >
>> >I suggest:
>> >
>> > cond ?? val1 || val2
cond -> val1 -> val2
which is short for
cond -> val1 >< True -> val2
which is a two-condition version of
cond -> val1 >< cond2 -> val2 >< cond3 -> val3 >< True -> valdefault
>>
>> +0.5
>>
>> I still have yet to see a clear explanation of why short-circuit is
>> necessary
>
>Short-circuit evaluation is never "necessary" in _any_ language - it's
>just very, very useful sometimes. Python's 'and' operator doesn't _have_
>to be a short-circuit operator, but it's far more useful because it is.
>
>> and therefore iif() unreasonable.
>
>Several of the previous examples have already illustrated this:
>
>z = iif(x, x.getPref(), 'Not specified')
z = x -> x.getPref() -> 'Not Specified'
>
>is broken without short-circuiting.
Regards,
Bengt Richter
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