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Re: Postfix conditionals

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On 1/5/2014 3:24 PM, Göktuğ Kayaalp wrote:
> Hi,
>
> AFAIK, we do not have "postfix conditionals" in Python, i.e. a condition
> appended to a
> statement, which determines whether the statement runs or not:
>
>    py> for i in [False]:
>    ...     break if not i
>
> The above piece of code is equivalent to this in Python:
>
>    py> for i in [False]:
>    ...    if not i
>    ...        break
>
> I believe that the first example is superior to the second example when
> the two is compared
> for readability and intuitiveness.  We already have a ternary statement

'conditional expression', which happens to be a ternary as opposed to 
binary expression.

> that looks similar,
>
>    py> print('hi') if True else None
>
> so I reckon there would be no breakage in old code if this kind of
> syntax was added.  Ruby has
> this, and AFAIK Perl also does.
>
> I lack the knowledge of whether the community has opinions on this kind
> of notation,

In general, negative on pure duplication. Guido has said he strongly 
dislikes the perl reverse if.

-- 
Terry Jan Reedy

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Re: Postfix conditionals Terry Reedy <tjreedy@udel.edu> - 2014-01-05 21:58 -0500

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