[Python-ideas] Aid reiteration with new class: gfic

Steven D'Aprano steve at pearwood.info
Sat Jun 20 11:24:12 CEST 2009

On Sat, 20 Jun 2009 01:55:42 pm John Graham wrote:

> Hrm, that leads to the question, is it mathematically possible to
> iterate over an infinite list... twice? :)

Mathematically, yes. Practically, no.

Mathematically, the trick is to ensure that the time it takes to iterate 
over each item approaches zero sufficiently fast. E.g. if it takes 1 
unit of time to process the first item, and 1/2 units of time for the 
second, and 1/4 for the third, 1/8 for the fourth, etc, then you can 
iterate over an infinite number of items in 2 units of time total. Then 
you can do them all again :)

Steven D'Aprano

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