[Python-ideas] math.inf and math.nan constants

[Devin Jeanpierre]

On Mon, Jan 12, 2015 at 11:40 AM, Zachary Ware
<zachary.ware+pyideas at gmail.com> wrote:
> On Mon, Jan 12, 2015 at 1:33 PM, MRAB <python at mrabarnett.plus.com> wrote:
>> I was going to say that calling it "isnan" is in keeping with
>> "isdigit", etc, but those are instance methods!
>>
>> So, why is it "math.isnan(x)" and not "x.isnan()"?
>
> I'm a little curious about this myself, since float.is_nan(),
> float.is_inf(), and float.is_finite() are all implemented, but #if 0'd
> out.

I'm not Christian, but adding methods to numbers can be annoying
because you may also have to add it to ints, rationals, decimals, the
numeric ABCs... At the very least, to ints, anyway.

-- Devin