[Python-Dev] range objects in 3.x

[Ethan Furman]

Steven D'Aprano wrote:
> Ethan Furman wrote:
> 
>> What about the idea of this signature?
>>
>> frange([start], stop, step=None, count=None)
>>
>> Then when count is desired, it can be specified, and when step is 
>> sufficient, no change is necessary.
> 
> A default of start=0 makes sense for integer range, because the most 
> common use for range *by far* is for counting, and in Python we count 0, 
> 1, 2, ... Similarly, we usually count every item, so a default step of 1 
> is useful.
> 
> But for numeric work, neither of those defaults are useful. This 
> proposed spread/frange/whatever function will be used for generating a 
> sequence of equally spaced numbers, and not for counting. A starting 
> value of 0.0 is generally no more special than any other starting value. 
> There is no good reason to single out default start=0. Likewise a 
> step-size of 1.0 is also arbitrary.
> 
> It isn't useful to hammer the square peg of numeric ranges into the 
> round hole of integer counts. We should not try to force this float 
> range to use the same API as builtin range.
> 
> (In hindsight, it is a shame that range is called "range" instead of 
> "count". itertools got the name right.)

Good points.  So how about:

some_name_here(start, stop, *, step=None, count=None)

?  I personally would use the step value far more often than the count 
value.

~Ethan~