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empty clause of for loops

Sven R. Kunze srkunze at mail.de
Wed Mar 16 10:39:41 EDT 2016 
On 16.03.2016 15:29, Sven R. Kunze wrote:
> On 16.03.2016 13:57, Peter Otten wrote:
>>
>> I'd put that the other way round: syntactical support for every pattern
>> would make for a rather unwieldy language. You have to choose 
>> carefully, and
>> this requirement could easily be fulfilled by a function, first in your
>> personal toolbox, then in a public libary, then in the stdlib.
>>
>> If you don't like exceptions implement (or find) something like
>>
>> items = peek(items)
>> if items.has_more():
>>     # at least one item
>>     for item in items:
>>         ...
>> else:
>>     # empty
>>
>> Only if such a function is used a lot or cannot be conceived without 
>> severe
>> shortcumings adding to the syntax should be considered. The 
>> (hypothetical)
>> question you should answer: which current feature would you throw out to
>> make room for your cool new addition?
>
> I am glad you asked. ;-)
>
> I would re-use the "for-else" for this. [Everything] I thought I could 
> make use of the "-else" clause, I was disappointed I couldn't.
>

[everytime]

>
> I find the addition to for-loop as useful as we already have a quite 
> complex try-except-else-finally clause. I don't know why for-loops 
> couldn't benefit from this as well.
>
>
> Best,
> Sven
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