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Subject: Re: Well, I finally ran into a Python Unicode problem, sort of
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Xref: csiph.com comp.lang.python:111008

On 2016-07-03 19:39, John Ladasky wrote:
> On Sunday, July 3, 2016 at 12:42:14 AM UTC-7, Chris Angelico wrote:
>> On Sun, Jul 3, 2016 at 4:58 PM, John Ladasky wrote:
>
>> Very good question! The detaily answer is here:
>>
>> https://docs.python.org/3/reference/lexical_analysis.html#identifiers
>>
>> > A philosophical question.  Why should any character be excluded from a variable name, besides the fact that it might also be an operator?
>>
>> In a way, that's exactly what's happening here. Python permits certain
>> categories of character as identifiers, leaving other categories
>> available for operators. Even though there aren't any non-ASCII
>> operators in a vanilla CPython, it's plausible that someone could
>> create a Python-based language with more operators (eg ≠ NOT EQUAL TO
>> as an alternative to !=), and I'm sure you'd agree that saying "≠ = 1"
>> is nonsensical.
>
> I agree that there are some characters in the Unicode definition that could (should?) be operators and, as such, disallowed in identifiers.  "≠", "≥" and "√" come to mind.  I don't know whether the Unicode "character properties" are assigned to the characters in a way that would be satisfying to the needs of programmers.  I'll do some reading.
>
>> Symbols like that are a bit of a
>> grey area, so you may find that you're starting a huge debate :)
>
> Oh, I can see that debate coming.  I know that not all of these characters are easily TYPED, and so I have to reach for a Unicode table to cut and paste them.  But once but and pasted, they are easily READ, and that's a big plus.
>
> Here's another worm for the can.  Would you rather read this...
>
> d = sqrt(x**2 + y**2)
>
> ...or this?
>
> d = √(x² + y²)
>
It's easy to read something as simple like that, but it's harder when 
the exponent is more than a number or a variable. And what about a**b**c?

Not to mention the limited number of superscript codepoints available...