[Python-ideas] Integrate some itertools into the Python syntax

[Ethan Furman]

On 03/22/2016 12:10 PM, Koos Zevenhoven wrote:
> On Tue, Mar 22, 2016 at 8:41 PM, Ethan Furman <ethan at stoneleaf.us> wrote:
>> On 03/22/2016 10:51 AM, Michel Desmoulin wrote:
>>
>>> def foo(p):
>>>       with open(p) as f:
>>>           def begin:
>>>               return x == "BEGIN SECTION"
>>>            def end:
>>>               return x == "STOP"
>>>           return f[begin, end][:10000]
>>>
>>> It's very clean, very convenient, very natural, and memory efficient.
>>
>>
>> Except the 10,000 limit doesn't happen until /after/ the end block is
>> reached -- which could be a million lines later.
>
>
> if f[begin, end] is a generator, the 10000 limit may happen before the
> end block is reached, which I think was the point.

That is wrong, which was my point: the `[:10000]` doesn't take effect 
until after `f[begin:end]` (whatever it is) is evaluated.

--
~Ethan~