Looping [was Re: Python and the need for speed]

Terry Reedy tjreedy at udel.edu
Mon Apr 17 09:05:20 EDT 2017

On 4/17/2017 3:11 AM, Marko Rauhamaa wrote:
> Gregory Ewing <greg.ewing at canterbury.ac.nz>:
>> bartc wrote:
>>> Most of my loops start off as endless loops, until I can determine
>>> the actual terminating condition, and where it best goes.
>> Interesting. My experience is quite different. Most of the loops I
>> write start off with me thinking "Now I want to do this for each
>> element of this collection", which maps straight to a Python for-loop.
>> In the rare cases where I do use a while loop, usually I have a fairly
>> good idea what the terminating condition is going to be.
> Here's statistics from a medium-sized project of mine:
>    while True:            34
>    while <condition>:     39
>    for ... in ...:       158

As I posted previously, the ratio of for-loops in the stdlib is about 7 
to 1.

Terry Jan Reedy

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